/V 4*4 • h '- HYDROGRAPHY OF THE ARID REGIONS. BY F. H. NEWELL. Digitized by the Internet Archive in 2017 with funding from University of Illinois Urbana-Champaign Alternates https://archive.org/details/hydrographyofariOOnewe CONTENTS. Hydrographic measurements and irrigation The arid regions Hydrographic data Deficiency of water Increase of water duty Water storage Relative amount of flood waters Time of floods Intensity of floods Rainfall and river flow Points of maximum utility Classification of drainage hasins Humidity and irrigation Evaporation observations Results of stream measurements Upper Missouri and Yellowstone Basins Platte Basin ; Arkansas Basin Rio Grande Basin Topography and elevations Annual and monthly rainfall The Colorado district of the Rio Grande San Luis Valley Irrigation practice The Taos district of the Rio Grande Tres Piedras Mesa Embudo gauging station Espanola Valley The Chama district Santa Ee district Albuquerque district Tributaries below the Chama Santa Fe and adjacent streams Jemez River Puerco River R6sum6 of water supply Mesas along the Rio Grande Mesilla Valley Gypsum Plains district Pecos River General topograj>hy Climate and water supply Upper tributaries 215 Page. 219 219 221 221 223 224 227 228 230 230 231 232 234 234 235 236 238 240 240 240 243 245 247 248 251 256 257 258 261 269 270 273 273 274 275 277 278 279 281 282 282 283 284 344433 216 CONTENTS. Page. Rio Grande Basin — Continued. Pecos River — Continued. Lower tributaries in New Mexico 286 Agriculture along tlie Pecos 287 Irrigation works on the Pecos 288 Colorado River drainage basin 290 The Gila Basin 292 Topography and altitudes 292 Agricultural lands 295 Duty of water - 296 Water storage 298 Rainfall 299 Upper Gila district 302 San Pedro district 303 Middle Gila district 305 Verde district 309 Upper Salt district 310 Lower Salt district «• 311 Lower Gila district , 314 Agua Fria and Hassayampa districts 315 Santa Cruz district 315 Sacramento and San Joaquin basins 316 Kern River 319 Tule River 319 Kaweah River 320 Kings River 320 San Joaquin River 321 Merced River 322 Tuolumne River 322 Mokelumne River 323 Lower San Joaquin River 323 The Great Basin 324 Truckee River 324 Carson River 325 Salt Lake Basin 325 Bear River 325 Bear Lake 327 Lower Bear River 329 Cache Valley 330 Ogden and Weber Rivers 334 Utah Lake drainage 334 Sevier River 339 Snake River drainage 344 Discharge tables 345 ILLUSTRATIONS. Page. Pl. LVIII. Index map of river measurements 222 LIX. Diagram of monthly river flow and rainfall 226 LX. Diagram of daily discharge of the West Gallatin River and Red Rock Creek, Montana 228 LXI. Diagram of daily discharge of the Madison River, Montana 230 LXII. Diagram of daily discharge of the Missouri River, Montana 232 LXIII. Diagram of daily discharge of the Sun River, Montana 234 LXIV. Diagram of daily discharge of the Yellowstone River, Montana . . 236 LXV. Diagram of daily discharge of the Cache la Poudre, Colorado, 1884 to 1891 238 LXVI. Diagram of daily discharge of the upper tributaries of the Arkan- sas River, Colorado, 1890 240 LXV1I. Diagram of daily discharge of the Arkansas River at Canyon City, Colorado, 1888 to 1891 242 LXVIII. Map of the Rio Grande and Pecos basins 244 LXIX. Earth columns near station at Embudo, New Mexico 246 LXX. Diagram of monthly rainfall in the Rio Grande Basin 248 LXXI. Diagram of daily discharge of the Rio Grande at Del Norte, Colo- rado 250 LXXII. Diagram of daily discharge of the Rio Grande at Embudo, New Mexico 256 LXXIII. Diagram of daily discharge of the Rio Grande at El Paso, Texas. 280 LXXIV. Diagram of gauge height of the Colorado River at Yuma, Arizona, 1880 to 1891 290 LXXV. Map of the Gila Basin, Arizona 292 LXXVI. Diagram of monthly rainfall in the Gila Basin, Arizona 300 LXXVII. View of the Hassayampa Reservoir, Arizona 302 LXXVIII. Diagram of daily discharge of the Gila River, Arizona 306 LXXIX. Diagram of daily discharge of the Salt River, Arizona 308 LXXX. Diagram of daily discharge of the Kern River, California, 1879 to 1882 310 LXXXI. Diagram of daily discharge of the Kaweah River, California, 1879 to 1882 312 LXXXII. Diagram of daily gauge height of the Kings River, California, 1880 to 1891 314 LXXXI1I. Diagram of daily discharge of the upper San Joaquin River, Cali- fornia, 1879 to 1882 316 LXXXIV. Diagram of daily gauge height of the upper San Joaquin River, California, 1880 to 1891 318 LXXXV. Diagram of daily discharge of the Merced River, California, 1879 to 1882 320 217 218 ILLUSTRATIONS. Page. Pl. LXXXVI. Diagram of daily discharge of the Tuolumne River, California, 1879 to 1882 322 LXXXVII. Diagram of daily discharge of the Mokelumne River, Califor- nia, 1879 to 1882 322 LXXXVIII. Diagram of daily gauge height of the lower San Joaquin River, California, 1880 to 1891 322 LXXXIX. Diagram of daily discharge of the Truckee and Little Truckee Rivers at Boca, California, and of Prosser Creek 324 XC. Diagram of daily discharge of the Truckee River at Vista, Ne- vada 324 XCI. Diagram of daily discharge of the Carson River at Empire, Nevada, aud of the East and West forks of the Carson 324 XCII. Map of the Bear River drainage basin 326 XCIII. View of the Bear River Canyon, Utah 328 XCI V. Diagram of daily discharge of the Bear River at Battle Creek, Idaho 330 XCV. Diagram of daily discharge of the Bear River at Collinston, Utah 332 XCVI. Diagram of daily discharge of the Ogden River, Utah 336 XCVII. Diagram of daily discharge of the Weber River, Utah 336 XCVIII. Diagram of daily discharge of the American Fork and Spanish Fork rivers, Utah 338 XCIX. Diagram of daily discharge of the Provo River, Utah 340 C. Diagram of daily discharge of the Sevier River, Utah 342 CI. Diagram of daily discharge of Henry Fork, Idaho 344 CII. Diagram of daily discharge of the Falls and Teton rivers, Idaho 344 CIII. Diagram of daily discharge of the Snake River, at Eagle Rock, Idaho 344 CIV. Diagram of daily discharge of the Owyhee River, Oregon 344 CV. Diagram of daily discharge of the Malheur River, Oregon 344 CVI. Diagram of daily discharge of the Weiser River, Idaho 344 Fig. 223. Diagram of annual rainfall in the Rio Grande Basin 244 224. Diagram illustrating sediment measurements at Embudo, New Mexico 258 225. An acequia at Roswell, New Mexico 289 226. Diagram of annual rainfall in the Gila Basin 300 227. Diagram of the daily gauge height of the Tule River, Califor- nia, 1879 and 1880 319 228. Diagram of daily gauge height of the Tuolumne River, Califor- nia, 1890 and 1891 322 229. Diagram of fluctuations of Utah Lake 336 HYDROGRAPHY OF THE ARID REGIONS. By F. H. Newell. HYDROGRAPHIC MEASUREMENTS AND IRRIGATION. The hydrographic investigations of the Geological Survey consist of measurements of the water flowing in the rivers or stored in the lakes of the United States, and, as far as possible, of a study of the laws which govern the distribution and fluctuation of the water supply. The greater part of these investigations are made in the western half of the United States, where flowing water possesses the greatest value and importance. In that part of the country the results of this work, besides being of scientific value, have direct practical application to irrigation and to the problems arising from the deficiency of water for agriculture and other needs of man, for upon the correct solution of these problems is dependent the growth and prosperity of this great division of the United States. In the eastern portion of the country hydrographic investigations are confined mainly to considerations of the flood discharge of rivers, for here the water supply is usually ample for all needs, and public interest is drawn to such subjects only through an excess of water so great as to be destructive. In the western part of the United States, however, the amount of water at low stages is the object of chief solicitude, and all the fluctuations are watched with care, for agricultural success or failure follows the prevalence of high or low water. THE ARID REGIONS. Over a large portion, perhaps one-lialf, of the continent of North America the rainfall is too small to support those forms of vegetation upon which man depends mainly for his supply of food. This great area, marked by a scanty plant life, lies in a general north and south direction, beginning in high latitudes, where the low temperature for- bids the growth of many species of plant life, and continues through the United States and into Mexico till cut off by the belt of tropical rains. The eastern border of this region of droughts is usually taken for convenience as coinciding with the one-liundredth meridian, and from this as the eastern limit it extends to the mountain ranges bordering the Pacific Ocean. This aridity of climate lias a fundamental influence 219 220 HYDROGRAPHY OF THE ARID REGIONS. upon the appearance of the country and upon the occupation of its inhabitants. There is perhaps no natural classification under which will fall more groups of facts than that of the division of the United States into these two great regions, the humid and the arid, for in them many of the political and social customs, as wel 1 as agriculture, must be radically different. In this vast area, containing great deposits of mineral wealth, and embracing agricultural land as rich as any on the globe, since the sup- ply of moisture is too small for the needs of man, the examination of all features which modify the water supply and the acquisition of knowledge of its present distribution and character have been recog- nized as being of great importance, for it is acknowledged that, although the water supply is at best scanty, its future use and efficiency can be greatly increased by a more intelligent utilization of the amount at present available. There is thus no investigation which bears more fundamentally upon the complete development of the resources of this great region than this careful examination and a recording of facts which are now known, to- gether with a study of the influences which may lead to a more thorough and economical employment of the waters. With our present informa- tion a report on these facts can not claim to be complete, but it is rather an introduction to the subject, which, while revealing the deficiency of our knowledge, demonstrates the great necessity of more careful and continued observations in the same line. The cause of the aridity of this vast area is traceable primarily to the general circulation of the atmosphere and to the shape and relief of the continent. This is perhaps best put by Ferrel in his “Popular Treatise on the Winds,” page 183, in which he states: If the whole surface of the earth were that of the ocean, or any smooth homogene- ous surface, the calm belts, the rain belt, and the dry zones would extend without interruption entirely around the globe with the same regularity which is observed upon the oceans, and everywhere the same climatic conditions would exist on the same parallels of latitude. But on account of the influence of mountain ranges in deflecting the currents of the general circulation of the atmosphere great diversities of (dimate are found in different places on the same parallels. It is thus on account of the topographic features of the continent, of the elevation and distribution of the mountain masses, that this arid land stretches in its general longitudinal direction instead of crossing the continent from west to east. Thus a full knowledge of the climate, and especially of the distribution of the rainfall not only in restricted lo- calities but on the continent as a whole, is largely dependent upon a correct understanding and representation of the general topographic features, for it is these which both in a broad and also in a local way are primary factors among causes which make. a country inhabitable and prosperous. Therefore, in this discussion of the hydrography of the arid lands, considerable space has been devoted to descriptions of topo- graphic features and local peculiarities, in order that all possible light might be cast upon seeming anomalies. NEWELL.] RIVER GAUGINGS. 221 HYDROGRAPHIC DATA. Upon navigable rivers in the United States measurements and other examinations have been and are being made under the direction of the Chief of Engineers, U. S. Army, all efforts being directed toward an improvement of navigation, the physical and geological problems receiv- ing less consideration. The character of the work is thus entirely dif- ferent in scope and results from that undertaken by the Geological Survey; but many of the details, especially of measurements of floods, are of great value in the physical investigations carried on by the latter. Beyond the field work of these two organizations of the General Gov- ernment a large amount of hydrographic information has been col- lected at various times, and many measurements of flowing waters have been made by engineers in the employ of the States, municipalities, or corporations, and this data, much of which is unpublished, would, if all could be brought together, prove of great value. For example, the state engineering department of California has published data con- cerning the principal rivers of that state; the State engineers of Colo- rado have done a similar work on a smaller scale; the northern trans- continental survey also acquired many facts in Montana, Idaho, and adjoining States, and various exploring parties in all parts of the West have occasionally gauged streams and estimated discharges. The results of many of these measurements will be discussed later, in con- nection with descriptions of the various drainage basins. The data collected from the sources just mentioned have been reduced to common units and arranged in form convenient for making compari- sons, and as many results as can be obtained at this time have been thus brought together and republished in condensed form, with brief explan- atory remarks. On the index map, PI. lyiii, is shown the location of the principal drainage basins and the points at which the gaugings referred to in subsequent discussions were made. During the year ending June 30, 1891, the Geological Survey received reports of the daily gauge height of many rivers of the West at points where gauging stations were previously established and discharge meas- urements made, and by this means the daily mean discharge at these several localities has been computed. These discharges afford a com- parison with those obtained in previous years, and add greatly to the knowledge of the regime of these rivers. On subsequent pages the results of these computations, are given and on the accompanying plates the daily discharges for various stations are shown in graphic form. In connection with these, the data obtained from other sources have been introduced in geographical order. DEFICIENCY OF WATER. As to the practical bearings of these investigations it is sufficient to state that the area cultivated by irrigation in most drainage basins of the arid region is far larger than can be covered by the present water 222 HYDROGRAPHY OF THE ARID REGIONS. supply, and each year the crops upon thousands of acres in various localities are injured or lost for lack of water at critical times. Besides this, there is a still greater acreage which can he reached by canal sys- tems constructed or projected, including bodies of land as good as that now under cultivation and sometimes better, and in addition to these irrigated aud irrigable lands there are in many parts of the arid region plains of arable land so vast that by no possibility can they ever be brought under irrigation. Thus as a whole the water supply can never be conserved too carefully, for there will always be fertile lands in ex- cess of that supply. With greater economy in the use of the present available water, a greater acreage each year can be successfully cultivated, but there will soon be a limit to the slow growth in this manner, for under ordinary circumstances it will happen that each year the amount of land suc- cessfully cultivated must fluctuate with the variations of water in the rivers; in years of large flow, the farmers will be prosperous, while, when droughts occur, a certain portion of the crops will be lost, if de- pendence is placed wholly upon the unregulated flow of the streams. There are, however, as above mentioned, floods at irregular intervals bringing with them great quantities of water. It has occurred to thousands of individuals, on seeing on the one hand rich soil lying barren for lack of moisture and on the other destructive torrents, that by the proper conservation of these floods, by saving the waste waters in times of need, not only will the farmer be able to raise all his crops, but, in addition, great tracts of land now unproductive may be made sources of wealth to the community. It is only a question of time, it may be live years or ftfty, when dams will be built to hold back this flood water, but the building of these will proceed slowly, for the con- ditions of success in such enterprises are entirely different from those pertaining to other irrigation projects. There can be nothing of an experimental, temporary nature in de- signing storage works as there is in the case of diversion dams in rivers or of canal works. They can not be essentially changed or modified, and the washing away of one is not a matter of loss to the owners alone, as with canal head works, but may involve the destruction of lives and property in distant localities. There are in the history of the last few years too many examples of this to call for further comment, and it is now generally recognized that not only must large sums of money be expended to construct these storage dams securely and permanently, but that a rigid inspection must be made by competent authorities. Before auy steps can be made toward the construction of such dams their builders must have ample and accurate information on which to base conclusive estimates as to the success of the enterprise. They must know, among other things, not only that the reservoir thus cre- ated will be of ample size, but that it has a reliable and sufficient water supply and that it will not be exposed to floods which can in any combination of circumstances tear it down. LIBRARY Of THE UNIVERSITY Of ILLINOIS U S GEOLOGICAL SURVEY. k fled Riv-ofth* ‘ 03 03 03 • a3 C/D r ft t- ^ Z a W g ft LlI cr □ Tj ^ J Cti 03 X £ 0) - 03 cd P ~ S? ® & g* > i ft r° £ w — ^ r O i ry- 03 cd ft 03 ft U li_ ft. oj 0 ° e ao ri 2 O 03 •r* 'GO cd _j U ft o y 1-1 ft 03 > 1 r 5 Sh CL < X LlI 0 £ •OC ti 600 Miles. LIBRARY OF THE UNIVERSITY OF ILLINOIS NEWELL.] DUTY OF WATER. 223 In most of the drainage basins where the typography is such that the floods are sudden and of short duration, the actual amount of water discharged by rivers is in general greatly overestimated, and before any notable reservoir can be made the question arises as to whether there is enough water to fill it. Our information on this point, though it is one which deeply concerns these basins, is unfortunately meager. The importance of the case, however, justifies a careful examination of the known facts and their publication. It is hoped that a discus- sion of these data may serve, perhaps, as a foundation for a protracted examination in the future, when there is a more general appreciation of the fact that the permanent agricultural growth of this land must await the completion of a long series of such careful observations. INCREASE OF WATER DUTY. Every improvement which tends to greater economy in the use of the present water supply adds ultimately to the acreage which can be cultivated. Water is wastefully used in many instances, there being a lack of economy in the methods of conducting it to the fields and in applying it to the soil. There are no inducements toward economy and no unity of action by which economy can be enforced. Each canal company or association of canal-owners is content if sufficient water can be procured to cover its own claim, regardless of the possible rights of others. In a case where a company sells water there is rarely any attempt to enforce economy, or inducement held out to users of the water to save it or make it cover the greatest possible extent of land. The common method of irrigating, especially when used on alfalfa and other forage crops and the small grains, is that of flooding, the water being caused to spread over the ground to an average depth of 2 to 3 inches or more. For other crops it is allowed to run along the furrows until the ground between each two furrows is saturated. For fruit trees or vineyards small trenches are plowed or dug leading from the lateral or small distributing ditch to each tree, the water being allowed to settle around the roots of the tree or vine. Experience, however, is gradually teaching the farmer that better success can often be obtained with small amounts of water intelligently applied than with greater, and also that as irrigation extends less and less water is required on many soils, this being due perhaps to a general raising of the moisture in the ground or to a clogging of many points of escape. The result is that less water per acre is used and needed on the older lands than on the newer. The area of land which can be irrigated by a given quantity of water is known for convenience as u the duty of the water.” The unit in general use is the second-foot, or cubic foot per second, that is, a quan- tity of water equaling a stream 1 foot wide and 1 foot deep, flowing at an average velocity of 1 foot every second. From what has been said, it is obvious that the duty of water varies much, being greater on 224 HYDROGRAPHY OF THE ARID REGIONS. old land tlian on new, and differing with the soils, as well as the skill and customs of the irrigators. There are unfortunately no reliable or detailed measurements to show what the actual water duty is. A number of estimates have been made, none of which agree very closely. Powell 1 in his first book on the arid lands gave the average water duty in Utah, under good con- ditions, as reaching 100 acres to the second-foot. The average of a number of estimates of the amount actually used in Utah, under or- dinary conditions and with little skill, was a trifle over two-thirds of this, or about 70 acres. In Wyoming and Idaho, where water was plentiful, land new, and irrigators unskilled, the duty was from 30 to 40 acres only. In Arizona and California calculations have been made that with care a second-foot can be made to cover 120 acres, or even more. Another way of expressing the duty of water is in acre-feet — the quantity of water covering an acre 1 foot in depth — 1 acre-foot thus being equivalent to 43,500 cubic feet. Thus a water duty of 1J acre- feet to the acre means that during the course of the irrigating season a quantity of water has been applied equal to a depth of 1£ feet over the ground. Some such arbitrarily selected duty of water is taken in all discussions as to the utility of water-storage systems, in order to com- pute the relation between their capacity and efficiency. It is evident that the duty of water will depend considerably upon the point at which water is measured. If, for example, water is meas- ured when entering the field where used, a higher duty will result than is found when the water is measured at the head of the canal, for in the latter case a certain quantity is lost by seepage and evaporation before it can reach the land on which it is to be employed. Further, a still less duty is shown if the water is measured in the river before entering the canals, unless, as is frequently the case, a certain amount returns to the river by seepage, to be used over again by land below. WATER STORAGE. Water storage for purposes of agriculture is comparatively new to the Arid Regions of the West, and is practiced to a small extent relatively to the whole area needing it. In order then to obtain certain definite ideas concerning relative costs and values, it would be useful to compare this with water storage as practiced in many parts of the country for municipal supply. The greater number of cities of the United States own or control reservoirs for holding the water, either for purposes of clearing it or as a safeguard against accident. One of the most important conceptions in connection with a compari- son between municipal supply and that for agricultural purposes is the vastly greater quantities needed and the less value of water for the latter use. The amount which is used in irrigation is so much greater than 1 Reports on tlie lands of the Arid Region of the United States, J. W. Powell, 2d ed., 1879, p. 84. HE WELL.] WATER STORAGE. 225 that needed by a city that it is difficult at first to comprehend the dif- ference, and many persons have been disappointed in their attempts at storage by failing to take into account in their original estimates the losses and waste which necessarily take place in connection with the free use of the water for agriculture. If it is assumed that 100 gallons per day is ample for each inhabitant of a small city, and, on the other hand, 1 acre foot is sufficient to irrigate 1 acre, a comparison can be made between the relative values of these two water supplies. One acre-foot equals 43,560 cubic feet, or about 326.000 gallons. Neglecting in both cases losses from evaporation, this 320.000 gallons on the above basis would supply 9 persons with water for a year. In other words, 1 acre-foot of stored water would either irrigate 1 acre, or, if carried to a city, would supply 9 persons, and 1 ,000 acre-feet would water 1,000 acres or supply a city of 9,000 inhabitants; but now if we compare the relative value of the property concerned the difference is at once apparent. The value of the irrigated land, at a liberal estimate, can not ordinarily be placed over $50 per acre, while the valuation of city property, taking the average for the United States for this number of inhabitants, would be about $5,000,000; that is to say, the property which must bear the expense of storing water is in the case of agriculture $50,000, and in the case of the city, needing the same amount, one hundred times as great, or $5,000,000. Taking these facts alone into consideration, it would seem that the city can afford to pay a vastly greater sum for storage, and can make use of opportunities for storage which are far too expensive for rural districts. There are many minor considerations which modify the above com- parison, but it is sufficient to demonstrate the general fact that for agri- cultural success water storage must be very cheap and of enormous capacity. The farmer can not afford to take the same chances of suc- cess or to repair injuries to the same extent that a city can, so that far greater caution, engineering skill, and foresight must be employed than in the case of our ordinary municipal supplies. In preliminary discussions of water storage for purposes of irrigation one of the most important facts to be borne in mind is that success does not. depend directly upon the quantity, distribution, or fluctuations of the rainfall. A full and exact knowledge of this subject is of course important and valuable as affording collateral data, but since the amount of water flowing in the stream is remotely affected by variations in rain- fall, these data can not be depended upon primarily. Comparing the rainfall and the snowfall, it may be said that precipitation in the form of snow is of greater importance than the rain to irrigation schemes, for the useful floods of most rivers are due rather to melting snow than to rainstorms. The time of the year at which snow falls, whether early or late in winter, and the temperature of early spring, have great influence upon the quantity and intensity of floods. This is seen on the various plates of discharge referred to in the following pages. By comparing 12 GEOL., PT. 2 15 226 HYDROGRAPHY OF THE ARID REGIONS. one with another it will be noted that melting snow furnishes the water necessary for great spring floods, this quantity being increased or dimin- ished day by day as the temperature rises or falls, so much so that iu cases where the river gauging station is near the headwaters of a stream the diagram of river discharges to a certain extent would serve as the diagram of fluctuations of temperature. PI. lix has been prepared to show, in condensed and generalized form, the lack of coincidence between the average discharge and the mean annual rainfall for each month of the year in four widely separated basins. In each of the four diagrams on this plate the dotted line rep- resents the mean annual rainfall, and the solid line the average height or discharge of the river. The months of the year are shown by vertical spaces, and horizontal lines give the height of water or quantity of dis- charge and also the depth of rain. In the upper diagram the mean discharge of the Cache la Poudre, above Fort Collins, for all years during which measurements have been made, is compared with the mean rainfall at Denver, Colorado, the assumption being made that rainfall at this station follows as a general rule the fluctuations within the basin of the Cache la Poudre. It will be seeu that the maximum amount of rainfall is in May, while the maxi- mum river flow is in the early part of June. The rainfall in June decreases, and then increases slightly in July and August. On the second diagram the mean discharge of the Rio Grande at Embudo, New Mexico, is compared with the mean annual rainfall at Santa Fe, although it is probable that the rainfall in the upper part of this basin has a habit intermediate between that at Denver and at Santa Fe. The river at this point reaches its maximum discharge earlier in the year than does the Cache la Poudre, and the rainfall, on the other hand, has its maximum in the early part of August. In the third diagram the mean gauge height of the Colorado River at Yuma, Arizona, is shown in connection with the rainfall at Prescott, Arizona. The maximum river height is reached in the early part of June at the time of minimum rainfall in the basin, the maximum rain- fall occurring about two months later, and usually causing little if any fluctuation in the height of the river. The low'est diagram on the plate shows the average height of the lower San Joaquin River in conjunction with the mean rainfall at Modesto, California. Here the maximum discharge occurs at about the same time as that of Cache la Poudre Creek and of the Colorado River, while the maximum rainfall is about the first of January. These four dotted lines of rainfall typify fairly well the distribution of rainfall in the arid region; on the east the maximum occurring in the summer, on the south the period of minimum rain occurring in May and June, and followed by heavy rain in July and August, at the time of the greatest droughts in California, The rivers, however, excepting in the case of those depending wholly upon local storms, have their regular spring floods independent of the distribution of rain. U. S. GEOLOGICAL SURVEY TWELFTH ANNUAL REPORT PL. LIX Jan. Feb. Mar. Apr. May. June. July Aug. Sept. Oct. Nov. Dec. Depth of rainfall. 2 inches. 1 inch. 2 inches. 1 inch. 3 inches. 2 inches. 1 inch. 3 inches. 2 inches. 1 inch. AVERAGE MONTHLY RIVER FLOW AND RAINFALL. LIBRARY OF THE UNIVERSITY OF ILLINOIS NEWELL.] QUANTITIES IN FLOODS. 227 RELATIVE AMOUNT OF FLOOD WATERS. In any discussion of hydrographic data, and especially its bearing on water conservation, one of the facts of primary importance is the rela- tion between the amount of water carried in floods and in low stages; in short, whether the river discharges in flood an amount greater by many times than that discharged during the remainder of the year, or whether the increase is comparatively small. For instance, taking a practical illustration, along most of the rivers of the West, as pre- viously stated, is an area of land greater than can be irrigated during the latter part of the crop season, and with an unregulated flow the area of land to be cultivated is governed by the low-water discharge of the river; and furthermore, all of this low water has in most cases been long ago appropriated. To bring more land under cultivation it is essen- tial, after practicing economy of the waters now available, to store some of the flood waters, and hold these until later in the season for use in time of need. The question of primary importance, then, is the amount of flood water relative to the ordinary discharge — whether it is sufficiently great to insure the success of storage works, and in time repay the cost of their construction by permanence of supply; or, on the other hand, whether the floods are so small in amount or irregular in occurrence as to be of doubtful value. It is really upon the flood waters that the greatest dependence for storage must be placed, for in many parts of the country the low- water discharge being appropriated and used dur- ing the most important season of the year, little reliance can be had upon this low-water flow during the remaining seasons. After the irrigating season is over, the amount of water flowing in the streams in the interval between that time and the beginning of the floods is usually small. In some parts of the country, especially in the south, the irrigating season extends practically throughout the year, and the water is used on the small grains, trees, and gardens, or for sat- urating the ground for the purpose of raising forage plants, when not otherwise needed. In many places, too, where the irrigating season is short, and extends only from four to six mouths, the water supply after the end of the irrigating season and between that time and the begin- ning of the floods is so small, or of such an uncertain character, as to be of doubtful value for storage purposes, the evaporation in many cases being sufficient to prevent an accumulation of water in any large storage basin. In short, then, it is to the amount and certainty of the flood waters that attention must be given in considerations of storage. The relation between the quantity in flood and in low water is shown graphically upon the discharge diagrams or hydrograplis of the various rivers, and it is instructive to compare these. The most conspicuous feature is the difference in character between the floods in rivers which receive their main water supply from melting snow and in rivers which depend wholly or in great part upon the rainfall. In the first case, as 228 HYDROGRAPHY OF THE ARID REGIONS. shown by the hydrographs in the Upper Missouri basin, the flood is seen to consist of a gradual continuous rise, and to increase in quantity un- til a maximum is reached, followed by an almost equally continuous de- cline. In the latter case, for example in the Gila basin, the floods are of an exceedingly irregular character, coming at any stage of the river and passing off rapidly, the river falling immediately again to low stage. The following table is given in order to exhibit in concise manner the relation between the mean discharge and the quantity of water carried in floods during the years in which measurements have been made. In the column at the right is the quotient, obtained by dividing the maximum discharge by the average quantity flowing in the stream. For example, in the case of the tirst river on the list, the West Gal- latin, the maximum flood reached a quantity four and five-tenths times the average annual discharge: River. Flood increase. River. Flood increase. 4-5 3 *9 3 2 Bear at Collinston 3 -2 3 6 ( igden 3 *4 5-9 4 4 2 -3 ] -8 6 -6 5 -3 4 -0 Rio Graiule at Del Norte 4-7 Henry Fork of Snake 4-4 6 1 3 7 11 -1 4 ‘3 12-6 100 -o 6 -8 4 *4 6 *3 6-2 6 -8 On looking down the list, it will be seen at a glance that on most of the rivers the flood has been from four to five times the volume of the average flow for the year. The most notable exceptions, however, are in the case of the Bio Grande at El Paso, the Gila, and the Salt, where the measured floods were over eleven or twelve times the average flow, and on the Salt Biver one hundred times, this latter case being that of the great flood of February, 1891. It is probable that if the measure- ments were continued for a period sufficiently long a far greater flood increase would be noted on some of the other streams. The three in- stances just noted, however, stand out clearly as illustrations of the wide fluctuations of the rain-fed rivers of the south. TIME OF FLOODS. The fact of secondary importance to that of the quantity of the floods for storage is the time at which they occur and the relation between the duration of high water and the time of growing crops. On most of the rivers of the West floods occur in the spring and di- minish in early summer. On some rivers they occur earlier and on others later, depending largely upon the altitude of the catchment basin. There is usually ample water at the time the crops are planted, DAILY DISCHARGE OF THE WEST GALLATIN RIVER AND OF RED ROCK CREEK, MONTANA. January. February. March. April. May. June. July. August. September. October. November. December. 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 library OF THE UNIVERSITY OF ILLINOIS NEWELL. ] TIME OF FLOODS. 229 so that there is no trouble in giving a first watering to all the land cul- tivated, but toward the end of the season, when the crops are maturing, the supply in the river diminishes, and often a portion of the crop is lost from lack of water at the critical time. As a rule it may be said that the later the floods occur the better for the success of crops and of storage schemes, for in the latter case the shorter is the time during which the water is held and the less will be the loss from evaporation. On the other hand, the earlier in the sea- son the floods occur the less water will be available for crops and the greater will be the loss by evaporation. The time is fast approaching when a large part of the flood water, excepting perhaps in a few great rivers like those of the Colorado drainage, will be held by storage from the early months of the year to July and August. In fact, much of this flood water is now needed, for the area of tilled land in many parts of the arid region is too great for the present supply in ordinary seasons, and unless some unusual storms occur, valuable areas of crops are lost. Besides these areas tilled, there are the tracts of fertile land so vast that the amount under cultivation shrinks into insignificance. Comparing, therefore, the rivers in their adaptability for supplying storage reservoirs as regards the time of flood, it will be seen that the most favorable instances are afforded by the streams of the northern basins bounded by lofty mountains, as, for - example, those of the upper Missouri and Arkansas basins, while, on the other hand, the streams draining the basins of less altitude are less favorable from this stand- point. In strong contrast to the rivers flowing into the Missouri in regard to the time of flood are those of southern or lower basins, as, for ex- ample, the Gila and Salt, or the Malheur and Owyhee in Oregon. As will be seen at a glance at the diagrams for the Gila basin, the time of floods is very uncertain, and while, as a general rule, the floods are more apt to occur in certain months, yet they cannot be relied upon as in the case of most northern rivers. Water storage in these rain-fed rivers, therefore, becomes more a matter of chance, and it is not possible to estimate within as narrow limits as in the case of the snow-fed streams the probable amount of water to be obtained each year. A comparison with the habits of the rivers outside of the arid region, as, for example, the Ohio or the Upper Mississippi, shows strongly the difference in the effect of the rainstorms, and illustrates the influence of topography and climate upon the discharge of a stream. On one extreme, that of the rivers in Arizona, the rain falls upon hard earth or barren rocks and slopes, which allow the water to flow off immediately. There is little or no vegetation to check or retain the water, and it rushes down the canyons and unites in the rivers, forming sudden floods. On the other extreme are the rivers of the humid region, rising in forested areas, where erosion has to a great extent cut down the higher moun- 230 HYDROGRAPHY OF THE ARID REGIONS. tains into rolling hills now covered with vegetation. The rain is held for a time, at least, by the soil, and slowly finds its way to the river, and the flood rises gently and diminishes so gradually that the effect of a heavy rain may be felt for days or weeks. INTENSITY OF FLOODS. The intesity of floods — that is, the relation between the quantity of water and the time during which the flood occurs — is involved in the two points above mentioned. It follows as a matter of course that on those rivers on which floods occur suddenly the rate of increase of water will be greatest and its destructive effects most apparent. In proportioning storage works and canals for diversion of flood waters, intensity, as well as quantity of flood, plays an important part, for, on the one hand, structures must be designed to withstand the sudden impetus of floods, and, on the other, diversion channels or waste weirs must be made of extraordinary size to provide for the passage of enor- mous quantities of water in a few hours. It is apparent that structures to withstand the onset of floods, shown diagram matically on many of the following plates, must be proportioned and executed in a manner which, to a person seeing only the low water, must seem extravagant. One fact particularly characteristic of the regions of intense floods is that river channels in size and general appearance bear very little ap- parent relation to the average daily discharge of streams which flow in them. In humid regions from inspection of a river channel an en- gineer can, in general, form a valid opinion as to the average amount of water which flows in it and the probable extent of the floods, but in the arid region, especially in the basins of lost rivers, the size of channel is entirely out of proportion to the amount of water which ordinarily flows in it, due to the extremely erratic conditions which pre- vail. For years or decades there may be a mere rill or at places no water in sight in the natural drainage lines, when, by a sudden storm or local “cloud-burst,” vast quantities of water will be precipitated, carv- ing in a few hours a channel of capacity for a navigable river. Thus it is that long observations are required to determine what may be the average flow of streams of this class and the quantity of water, if any, which can be depended upon from year to year. RAINFALL AND RIVER FLOW. The amount of water flowing in the river each day does not depend directly upon the rainfall of the preceding days, but upon many modi- fying conditions, and a storm, although widespread and reported at all stations, may not show itself by greatly increasing the amount of water passing any given point on the river. On the other hand, a storm so local that it is not reported by observers may cause a decided increase in the amount of water available, or even a destructive flood. In examining the depth of run-off- — that is, the quantity of water dis- DAILY DISCHARGE OF THE MADISON RIVER AT RED BLUFF, MONTANA. GEOLOGICAL SURVEY TWELFTH ANNUAL REPORT PL. LXI LIBRARY OF THE UNIVERSITY OF ILLINOIS NEWELL.] CHARACTER OF DRAINAGE BASINS. 231 charged equivalent to a certain depth over any given basin — it will usually be seen that the larger the area the less is the relative amount discharged, and this is especially the case in those parts of the country where evaporation is notably greater than rainfall. The rivers increase in size to a certain point as they flow down the broad sandy channels and then decrease, excepting in times of unusual floods. Even in those parts of the country where rainfall is great and evaporation of less importance this general law seems to hold good, namely, that the rivers do not increase in volume in direct proportion to the area drained, but that the ratio of discharge to area is, in a general way, decreasing from the headwaters toward the outlet. This fact must be borne in mind in these comparisons, and due allowance made for the point on the river’s course at which measurements are made. POINTS OF MAXIMUM UTILITY. There is a general similarity among the rivers under discussion in that they rise in great mountains and flow as torrents through narrow valleys, gorges, and canyons, entering finally upon plains of vast extent and with nearly level surfaces. On account of the great altitude the sources of the river are usually in a cold and an inhospitable region where great bodies of snow accumulate during the winter, and the frosts, which occur perhaps every month of the summer, render ag- riculture entirely out of the question. Below this upper region are often valleys which, though still of considerable altitude, are suitable for grazing, and in which a few of the hardier crops can be raised. Here also is found the most valuable timber, and the climate, though rigorous, is favorable for habitation, so that settlers, if forced from the lower regions from lack of water or other causes, find here place for homes and opportunities for earning a livelihood. These valleys also are most favorably situated for storage reservoirs, many of glacial origin seeming to be thus designed by nature. Farther down, beyond the canyons, stretch the wide, open valleys, and out beyond these the rich alluvial soil of the plains. It is here at these lower altitudes with a warm, sunny climate that agriculture is most successful, and here a given amount of water properly used will raise crops of the greatest value. In these places, near the foot of moun- tains, the water flows in well defined channels with high confining banks. Farther out upon the plains, however, the character of the river and its channel change. The silt deposited by the diminished velocity chokes the bed of the river, and the water spreads over a great expanse of sands, dividing and subdividing into numerous shallow streams whose united width may be more than a mile, but whose depth at ordinary stages is scarcely over a foot. Iu these sands enormous quantities of water disappear by seepage and evaporation, until finally, in seasons of low water, the channel becomes almost if not completely dry. The conveyance, therefore, of water through this channel to land far out 232 HYDROGRAPHY OF THE ARID REGIONS. on the plain involves a wasting of the greater portion in order that a small part may reach the desired locality. From the above considerations alone it will be seen that the point from which water can be used to the greatest advantage is that at which the stream begins to change in character, to lose its well defined chan- nel and sink in the sand of the bed, for at this point the river is carry- ing its maximum amount of water. The land here is usually as fertile as any on the plains, while the opportunities for caual building in the gently sloping edges of the plains are most favorable both for taking out the water at the smallest cost and for covering the largest extent of land. If the water is diverted far above this point it is used with less econ- omy and, on account of the altitude, the crops raised are of less value, while below this point on the open plain the wastage of water required for its conveyance in sandy channels results in loss, which is iu general proportional to the distance to be covered. The chief interest, there- fore, centers on the examination and measurement of the streams as they leave the canyons, and, secondary to this, on similar work in the upper valleys, where the great storage sites are found. CLASSIFICATION OF DRAINAGE BASINS. Hydrographic basins are divided by Powell into three classes, viz: Headwater districts, river trunk districts, and lost stream districts. The headwater districts include the sources of the river in the high mountains, including thus the torrential portion, and also the land used for farming immediately adjoining the river where it leaves the moun- tains. In a large river system this is the most important and most in- teresting portion of its course, from the standpoint of irrigation. Each large perennial tributary of the river thus becomes a district by itself, and can be considered independently in any discussion of the hydrogra- phy of the region. The river trunk district includes the great area through which the main stream flows, but from which the stream receives little or no water. This vast area, in fact, instead of contributing to the flow, leads only to its dissipation, for, in passing through the wide valleys or plains which constitute this portion, much of the water is lost by seepage and evap- oration. The trunk stream district can not be considered by itself, but must be governed largely by the conditions existing in all of the head- water districts, and it is only after the problems connected with the headwaters have been satisfactorily settled that the main stream can be treated in the best manner. The third class of basin, which in the west is one of the most impor- tant and perhaps most easily controlled, is that of the lost river. In this the circulation of waters is complete within itself, that is, the water coming from the atmosphere in the form of rain or snow gathers on the mountain slopes and flows in torrents to the plains, where it again dis- DAILY DISCHARGE OF THE MISSOURI RIVER AT CRAIG, MONTANA. January. February. March. April. May. June. July. August. September. October. November. December 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 LIBRARY OF THE UNIVERSITY OF ILLINOIS NEWELL. ] DRAINAGE BASINS CLASSIFIED. 233 appears, finally returning to the air by evaporation. Thus each basin can be considered independently, since the proper utilization of its waters does not effect any other basin except in the most remote manner. All these classes of basins are represented in many of the great river systems, in the Arkansas, the Rio Grande, the Gila, and others, each embracing within its scope many minor basins, some tributary to the river and others entirely lost. Each of these subbasins constitutes a unit, and, while the lost river basin may be considered as an independent unit, the others are factors, upon the proper application of which de- pends the final solution of the problem as to the best manner of utiliz- ing the water supply. Each one must be carefully studied in turn, its limits clearly defined, and all the characteristics known. Within each of these basins the problems of water supply are to be studied for the whole area, as each part is intimately connected with every other, and whatever affects one locality influences the rest. A storage work built on a minor tributary, siuce it tends to diminish the water at one time and increase it at another, is of importance to the majority ofinhabi- tants of that particular basin. Considering all the subbasins, the in- fluence of one upon the other varies with their character. For example, the headwater basins, as a whole, must be considered in connection with works of improvement on the trunk-stream basins, while, on the contrary, the lost-stream basins, being units which stand entirely inde- pendent of the rest of the country, need less consideration, excepting as they may influence the wealth and population in a general way. The headwater and lost-stream districts are easily recognized, being plainly marked by nature and separated from each other by mountain ranges or lower divides shown by the topographic maps. The main- stream districts, however, are not so clearly delimited, for the lines bounding them are somewhat arbitrary in their nature, so that careful study must be given to the conditions which govern them. The lost rivers, though found scattered throughout the west in nearly all of the large drainage basins, are most numerous and in fact are dis- tinctive of the great interior basin. Within this area not a drop of water escapes to the sea; the rain descending upon the mountain flows for a time in streams, then finally passes into the air again, is carried by the wind, which perhaps striking against some great escarpment is deflected upward and the moisture again precipitated enters upon a new round of river life, this round being repeated again and again, the individual molecule of water perhaps passing through innumerable changes of condition, until finally it travels out of the basin to be re- placed by moisture which is continually entering, mainly from the Pa- cific side. In this round of existence a portion of the moisture is caught and held for an indefinite time in the sands or gravels of the river bot- toms which are saturated by percolation from the running streams. These layers of porous material form reservoirs from which wells and springs are supplied, the amount of water delivered by these wells and 234 HYDROGRAPHY OF THE ARID REGIONS. springs being in a general way proportional to the extent and permea- bility of the sands and gravels. HUMIDITY AND IRRIGATION. There is a popular belief that by spreading the water on the surface of the ground through irrigation the rainfall is increased by the addi- tion of this water to the air through evaporation. There is no question that evaporation from the soil, especially from large tracts of cultivated land, must tend to lower the temperature near the surface and make the air far more humid, so that, as far as the feelings or sensations of man go, irrigation and consequent evaporation may tend to modify the temperature and make it better adapted for the comfort of man in the immediate vicinity of his operations. But, as for modifying the climate as a whole or bringing about such changes as will cause an increased rainfall, it is doubtful if these operations can have the slightest in- fluence, especially if the relative bulk of water contained in the air is compared with that which is added to the ground and escapes by evap- oration, to increase the amount and percentage of that already there. In this connection it is interesting to note that inland lakes, with their vast bodies of water continually adding moisture to the air, increase the rainfall only to a slight extent, if any, around their borders. If these vast stretches of water do not have a decided and perceptible influence upon the rainfall of a country, it seems hardly possible that the smaller scattered areas of earth moistened by irrigation, in extent hardly 1 per cent of the entire area of any one county, can have any measurable in- fluence upon the distribution of rain. The benefits to be derived are, however, not dependent upon increasing the humidity of the atmosphere as a whole, but only of that minute fraction of it which happens to be in immediate contact with the parts of the earth’s surface utilized by man. In short, in all water conservation, the first efforts should be directed toward making the largest use of the present available moisture, pre- venting losses by evaporation not only in the flowing water, but in the fields, by means of proper tilling and by sheltering the soil, and after that by increasing the available supply by storing floods, and by mak- ing use of other sources which require engineering skill and the invest- ment of capital. EVAPORATION OBSERVATIONS. The evaporation observations described in the previous annual report have been continued in the same manner at Fort Douglas, the military post near Salt Lake City, Utah, at Fort Bliss, about a mile above El Paso, Tex., and also at Tempe, Ariz. The results obtained at these three places, together with those of previous years, are given in the fol- lowing table. DAILY DISCHARGE OF THE SUN RIVER 18 MILES ABOVE AUGUSTA, MONTANA. TWELFTH ANNUAL REPORT PL. LXIII LIBRARY OF THE UNIVERSITY OF ILLINOIS NEWELL.] STREAM MEASUREMENTS. 235 'Monthly totals of evaporation from large pans. Months. Fort Douglas, Utah. 3889. 1890. 1891 Fort Bliss, Texas. 1889. Tempe Arizona. 1889. I 1890. I 1891. Inches. Inches. Inches. Inches. January . February March . . . Inches. 2-0 2-0 7 0 Inches. 2-7 2 9 5 5 Inches. Inches. Inches. 3-9 3 '6 3-7 April 3'7 3 '2 May 41 4 8 Juue 5 1 -5-2 July August . . . September October . . . November December . ; 7-6 / 0 10-5 1 6-5 6-5 5 7 4-6 5*2 4-9 2 J 2 -5 10 1-2 1-4 11 9 6 8 4 6 2 9 7-3 7-4 10-8 11 -7 9-6 7-6 13-7 14 1 11 0 6 4 3 7 4 4 3-0 5-5 5 6 6 6 11-5 5-8 5-2 4 6 3 2 RESULTS OF STREAM MEASUREMENTS. In the following pages the data for the various drainage basins are presented in geographical order, beginning at the headwaters of the Missiouri and continuing southward, taking in turn the Yellowstone, Platte, Arkansas, Rio Grande, and Colorado River basins, then the San Joaquin and Sacramento, the Interior Basin, and finally the Snake drainage. In each of these the order of arrangement is from the head- waters toward the mouth. In the case of the Rio Grande, Gila, and Salt Lake basins a description of the topography and its relation to the water supply is given with some degree of minuteness. Descriptions of the gauging stations, and the results of the measure- ments in these basins up to June 1890, have been published in the Eleventh Annual Report of the Director of the U. S. Geological Survey, Part it, together with comments upon the local topography and climate. Since the time of that publication readings of gauge height have been maintained at the principal localities mentioned in that report, enabling computations to be made of the daily mean discharge at those places, thus affording opportunity for comparison of the amount of water flow- ing in the years 1889 and 1890. The daily discharges of the streams measured in these basins are shown in diagrammatic form on the accompanying plates. The irregular lines indicate by their position the amount of water flowing on each day of the years given. The days are indicated by the spaces from left to right, in general each fifth day of the month being designated by a ver- tical line. The amount of water flowing on intermediate days can be ascertained by dividing these spaces by the eye into fifths. In the case of the months having thirty-one days the space from the twenty-fifth day to the first of the next month is proportionally wider than the others, and in the ease of the last three days in February proportionally narrower. The height of the curved line above the base indicates the average amount of water in cubic feet per second flowing on the particular day considered. Thus these diagrams show not only the amount of water on any given date, but also the amount relative to that of the whole year or series of years, and to that of other rivers. The average 236 HYDROGRAPHY OF THE ARID REGIONS. monthly discharges, or at least such as have not been published in the previous report, are given in condensed form at the conclusion of this paper. UPPER MISSOURI AND YELLOWSTONE. On PI. lx the discharges for the West Gallatin, southwest of Boze- man, Montana, and for Red Rock Creek, a tributary of the Jefferson, are given together, since the discharge of the latter is so small that it does not interfere with the clearness of the diagram. The discharges of the West Gallatin during September and October of 1889 are given, being indicated by a line of dots and dashes. This discharge, as can be seen, was nearly 200 second-feet less than in the succeeding year. The measurements in 1891, beginning in the early part of May, show a less discharge than that of 1890. The discharge of the Madison, near Red Bluff, Montana, is shown on PI. lxi, the most noticeable feature being the comparative regularity of the small oscillations during all the months of the year excepting those of the spring floods. The discharge of 1891, as in the case of the other rivers, is decidedly less than 1890. The amount of water in the Missouri River at Craig, as shown on PI. lxii, is in 1891 nearly equal to that of 1890, the lower discharge of the tributaries, however, beiug noticeable even in the case of the main stream. The relative location of these stations can be seen on the small map, PI. lviii, which also gives in a general way the relative size of the areas drained. The discharge of the Sun River above Augusta, Montana, is shown on PI. lxiii. A record has been kept of only one flood season, that of 1890, and therefore comparisons can not be made. It is probable, how- ever, that this series of measurements represents fairly well the ordi- nary behavior of the river. The low water of the fall of 1889 is shown on the diagram, it being in amount decidedly less than that of 1890. It is interesting to compare the results given on the diagrams and in the tables with those obtained in other years. The earliest recorded gaugings were made in 1872 by Thomas P. Roberts, assistant engineer on the Union Pacific Railroad. 1 He found that the Gallatin was flow- ing in the latter part of July, 1872, at the rate of 2,090 second-feet, the Madison 2,670 second-feet, and the Jefferson 3,778, making in all 8,538 second-feet. According to Roberts’s judgment, the lowest water of September and October was about 0,600 second-feet, and the highest in the middle or last of May, 33,300 second-feet, both amounts being, however, far greater than obtained by later measurements. On July 31, 1872, the measured discharge at a point 71 miles below the Three Forks was 10,000 second feet, and on August 12, at Fort Benton, 11,132 1 Report of a Reeonnoissance of the Missouri River in 1872. by Thomas R. Roberts, assistant engineer Union I’aeific Railroad. Printed for the use of tho Engineer Department, U. S. Army, 1875. DAILY DISCHARGE OF THE YELLOWSTONE RIVER AT HORR, MONTANA. TWELFTH ANNUAL REPORT PL. LXIV library OF THE UNIVERSITY OF ILLINOIS NEWELL.] GAUGINGS OF THE MISSOURI RIVER. 237 second-feet , 1 the amount of these discharges relative to the results ob- tained by recent measurements being shown on PI. lxii. In 1882 gaugings were made by the Engineer Corps, U. S. Army, at Stubbs Ferry, 73 miles below the Three Forks, and 12 miles from Hel- ena, and of the three principal tributaries entering below Stubbs Ferry. The discharge at this place was, at a stage of 0-5 feet, 3,770 second-feet; of the Dearborn, at high water in the Missouri, G22 second-feet; of Deep Creek, at 2-75 stage of Missouri, 1,800 second-feet, and of the Sun River, at 3-05 feet in Missouri, 4,270 second-feet. The total discharge of the Missouri just below the mouth of the Sun River, or about 50 miles above Fort Benton, was, for a stage of 3-05 feet, 19,425 second-feet. 2 In 1878 a gauging was made at Dauphin Rapids, 95 miles below Fort Benton and about 12 miles below Judith River. The discharge was 11,002 second-feet 3 from a drainage area of 39,247 square miles. 4 It was estimated that the mean daily discharge in 1879 was 13,530 second feet, and in 1880 was 18,151 second-feet. Comparing this with the mean annual rainfall in these years,, which was assumed to be 15-80 inches and 10-88 inches, respectively, in the basin, the run-off was computed to be 30 per cent of the rainfall in 1879, and 37 per cent in 1880, 5 6 or a depth of 4-87 inches and 0-30 inches in these respective years. On October 20, 1882, a measurement was made at Ryan Island, 72 miles below the above-mentioned locality, and about 30 miles above the mouth of the Musselshell River, the drainage area being estimated to be 39,905 square miles. The discharge was 7,305 second-feet at a stage of 0-87 foot above low water of 1874.° In the fall of 1890 a few stream measurements were made by Mr. G. A. Marr, assistant engineer of the Missouri River Commission, while carrying on careful leveling from Three Forks to Fort Benton, Montana. These gaugings, although considered approximate merely, are given in connection with other data, because they afford material for further study. The first of these is the measurement of July 28, 1890, made above the Three Forks, when it was found that the Gallatin discharged 730 second-feet and the three streams — the Gallatin, Madison, and Jef- erson — aggregated 2,803 second-feet. The second measurement was on August 0, 1890, on the Missouri, just below Gallatin, the total dis- charge being 2,400 second-feet, and the third on September 18, 1890, near Canyon Ferry, giving 2,082 second-feet. The daily discharge of the Yellowstone River below the National Park is given in graphic form on PI. lxv. The measurements were made about 0 miles below the town of Cinnabar, at Horr, a station de- scribed in a previous report. As shown on this plate, the discharge for 1891 is similar to that for 1890, but is, in general, a little less. 1 Report of a reconnoissanoe of the Missouri River, etc., p. 54. 2 Annual Report of the Chief of Engineers, XT. S. Army, 1883, p. 1340. 3 Ibid., 1878, p. 699. * Ibid., 1883, p. 1353. 6 Ibid., p. 1353, et seq. 6 Ibid., p. 1354. 238 HYDROGRAPHY OF THE ARID REGIONS. Many of the tributaries of the Yellowstone, especially those heading in Wyoming, are of great importance in irrigation, their waters in the summer being entirely diverted upon the fertile lands along the valleys. The State engineer of Wyoming, under authority of recent legislation, has gauged some of these streams for the purpose, primarily, of obtain- ing information by which to determine the rights of the various canals and ditches claiming the waters. In this manner a body of data is being acquired concerning these tributaries, which, however, has not as yet been published. For example, a permanent gauging station has been established on Clear Creek, near Buffalo, Wyoming, this stream, a tributary of Powder River, supplying water for a part of one of the most important agricultural areas in the State. In the annual report of the State engineer for 1890 it is stated that, upon explaining to some of the public-spirited citizens of that vicinity the importance of a gauging station and the inability of the engineer to establish it on account of the lack of appropriation from the State, the citizens imme- diately volunteered to assist in the work, and an arrangement was made by which they undertook the construction of a weir. Pending the completion of the weir, a temporary gauging station was estab- lished, and daily readings are taken of the discharge of the stream. The discharge of the Yellowstone was measured in August, 1879, at the mouth of the Big Horn, at a stage of 1-70 feet above low water of 1878, giving for the Big Horn 5,865 second-feet, for the upper Yellow- stone 7,471 second-feet, and total discharge below the Big Horn 13,336 second-feet. At Fort Keogh, 100 miles by river below the Big Horn, the discharge in September, 1878, was 14,462 second-feet, in October, 1879, was 6,505 secoml-feet, and in 1883, at about the same stage, 6,015 second-feet. At Wolf Rapids, 50 miles below, in September, 1878, gaugings gave 11,235 second-feet, and at Diamond Island, 100 miles by river below Wolf Rapids, in October, 1878, the discharge was 8,155 second feet. 1 The total drainage area of the Yellowstone is 69,683 square miles, and of the Missouri, above the mouth of the Yellowstone, 95,093 square miles. The data for the total discharge of the Upper Missouri and Yellowstone are not sufficiently extended to enable exact compari- sons to be made, but from inspection of the foregoing it appears that the quantity of water in the two streams is about equal. PLATTE BASIN. The most important series of measurements in this drainage basin are those being made on the Cache la Poudre, about 12 miles above Fort Collins, Colorado. These have been fully described in the pre- vious report, and the results given up to June 30, 1890. The diagrams on PI. lxv show graphically the daily discharges up to the present time and afford a means of comparing one year with another. Annual Report of the Chief of Engineers, U. S. Army, 1880, p. 1476, and 1883, p. 1342. LIBRARY OF THE UNIVERSITY OF ILLINOIS January. February. March. April. May. June. July. August. September. October. November. December. U. S. GEOLOGICAL SURVEY !QQ4- /88S TWELFTH ANNUAL REPORT PL. LXV DAILY DISCHARGE OF THE CACHE LA POUDRE 12 MILES ABOVE FORT COLLINS, COLORADO, 1884 TO 1891. LIBRARY NEWELL.] GAUGINGS OF PLATTE RIVER. 239 For clearness these data have been placed on two diagrams, the dis- charges for 1884, 1885, 1886, and 1887 being placed on one page, and those for 1888, 1889, and 1890 on the other. In addition to these discharges for individual years, the line showing the average daily discharge has been plotted on both diagrams. This curve shown by heavy dots and dashes has been obtained by combining the results for each year since the beginning of the observations. The discharges for 1884 and 1885 come far above this line, while those for 1886 and 1887 agree with it fairly well. During the years succeeding these, however, the flood discharge does not at any time reach this line, showing the great diminution in flow for the last three years. The fluctuations and uses of the waters of the Cache la Poudre are discussed by Prof. L. Cl. Carpenter in the annual reports of the Colo- rado State Agricultural College at Fort Collins. 1 Other measurements of flowing water have been made at various points in the Platte basin, these, however, being mainly disconnected and fragmentary. Mr. Henry Gannett, in the Hayden 2 report for 1876, gives the results of a number made on tributaries heading near the continental divide. The State engineer of Wyoming has also made a number of gaugings of the Laramie and other rivers, and has established gauging stations, the results of which promise to be of value. A permanent station on the Laramie was established in December, 1888, at Woods, near the southwestern corner of Albany County, about 30 miles above Laramie City. During the following winter and up to April 1, 1889, the discharge was approximately 112 second-feet. The maximum for the year, 1,620 second-feet, occurred in June, falling from this to a minimum of 43 second-feet in September. A smaller quantity of water was discharged in that year than ever before known, the maximum in some seasons being over 6,000 second-feet. The North Platte was gauged by Mr. A. M. Van Auken, civil engi- neer, near Fort Laramie, Wyoming, in 1887, 1888, and 1889, and also near the Wyoming- Nebraska line during the low stages of 1890, the velocities in each instance being obtained by means of floats. The re- sults are not considered by him to be more than approximations, but as such they have their value, and with this qualification they are here- with given. It is believed by Mr. Van Auken that these figures will give a fair idea of the discharge of the stream, and that the results are more accurate for the smaller discharges than for the larger. 1 The State Agricultural College of the State of Colorado. Third annual report of the agricultural experiement station, 1890 . Fort Collins, Colo., p. 58 . 2 Tenth Annual Report of the U. S. Geol. and Geog. Survey of the Territories, F. V. Uayden. 1870, pp. 323-326. 240 HYDROGRAPHY OF THE ARID REGIONS. North Platte Hirer. Month. Discharge. Max. Min. Mean. 1887. Sec. f. Sec./. Sec./. May 8, 240 3, 520 5, 255 June 10, 140 7, 680 8, 995 July 7, 680 3,640 5, 676 August 3, 720 3, 380 3, 560 1888. May 4, 510 3,780 3, 991 June 1 to 21 6, 490 3, 920 5, 671 July 11 to 31 6, 060 4,280 4,711 August 5, 180 3, 900 4. 341 September 3, 920 3,430 3, 822 October 1 to 22 3, 920 3,110 3,517 1889. April 3,438 2, 970 3, 208 May 8, 120 2, 960 4,216 Month. 1889 — Continued. June July August September October November 1 to 15 . . . 1890. March April May June July August September 1 to 6 Discharge. Max. Min. Mean. Sec. f. Sec. f. Sec. /. 10, 260 5, 170 8. 240 6,080 4,240 5, 506 4, 290 3.220 3, 498 3, 240 2. 580 2. 892 3,210 2,430 2, 859 3, 960 2, 370 3. 205 3,400 3, 180 3,316 3, 720 3,200 3.457 6, 970 3, 840 5, 151 10, 240 8, 180 8.682 7, 960 5, 120 6, 469 5, 425 3, 380 4, 160 3, 680 3, 440 3,560 ARKANSAS BASIN. The gauging stations in this basin were described in the last annual report of this Survey, to which reference should be made for details re- garding the measurements up to that time. The results of these measurements and computations of discharge for the upper tributaries of the Arkansas are given on PI. lxvi, and for the Canyon City sta- tion on PI. lxvii. Referring to this plate, it will be seen that the most notable fact is the increased discharge during the spring of 1891. This is al.so brought out by the table of monthly discharges given on page 849. No measurements have been made of the discharge at sta- tions on the lower Arkansas since 1889. The gauge heights at these stations have been published in diagrammatic form in comparison with the rainfall in the basin in the previous annual report. (PI. lxxi. Eleventh Ann. Rep. U. S. Geol. Survey, part ii.) RIO GRANDE BASIN. TOPOGRAPHY AND ELEVATIONS. A study of the hydrography of the Rio Grande Basin, PI. lxviii, and of its facilities for water conservation offers some of the most in- teresting problems undertaken by the Geological Survey. This is due not only to the large extent of area covered by this basin, but also to the wide difference in topography and character of soil and climate. The matter is further complicated by the relation of political divisions, State and county lines, to the basin as a whole. This discussion of the Rio Grande Basin, including the subbasin of the Pecos, its largest tributary, is confined to that portion lying within the State of Colorado and the Territory of New Mexico, the part in Texas possessing a smaller interest in this connection. The total area in these three political divisions above the junction of the Pecos with the Rio Grande is, approximately, 145,200 square miles. Not all of the area embraced within the limits of this great topographic basin con- tributes water to the river, but on the contrary, there are extensive DAILY DISCHARGE OF THE UPPER TRIBUTARIES OF THE ARKANSAS RIVER, 1890. January. February. March. April. May. June. July. August. September. October. November. December. 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 • 5 10 15 20 21 LIBrtARy OF THE UNIVERSITY OF ILLINOIS NEWELL.] TOPOGRAPHY OF RIO GRANDE BASIN. 241 tracts, as in the case of all the southern basins of the arid region, from which there is no outflow. The total area north of the Texas-New Mexico line, including the lost river basins, is 89,100 square miles, and that portion in Colorado included in the above measurement is 7,527 square miles. The largest part of the water flowing in the Eio Grande comes from the mountains of Eio Grande and Conejos Counties, Colorado, and also, though to a less degree, from the mountains in Costilla County. The river reaches its maximum, considering all seasons of the year, at a point not far from its headwaters, for after flowing through the San Luis Park and entering New Mexico the various tributaries, though draining large areas, do not contribute a notable amount to the stream excepting in times of floods, and on the other hand there is a constant loss by evaporation and artificial diversions. The Eio Grande Basin is a long, narrow strip of country, the peren- nial supply of water coming principally from a comparatively small area of about 2,000 square miles of lofty mountains. The greater part of the remaining catchment contributes water only in times of flood, that is, in the months of May and June, while during the rest of the year the waters falling within this area or coming from melting snows do not reach the trunk stream, but are evaporated or sink into the sands. In addition to the areas contributing a perennial supply of water and a spasmodic supply, there is a vast area of lost river basins from which, as mentioned before, no water comes at any time, but which from topographic features may be included within this great catchment basin. The following descriptions of these topographic features and the character of the water supply of the subbasins embraced within the Eio Grande drainage system were taken from reports made at various times by assistants who were engaged in water measurements or pre- liminary examinations for reservoir sites. Among these were Messrs. L. D. Hopson, G. T. Quinby, E. S. Tarr, W. W. Follett, and H. M. Dyar. In order to condense and unify this material and combine it with data from all sources, the individual reports have not been designated, but they have been inserted as needed in geographical order. The Eio Grande rises in southwestern Colorado (PI. lxviii), flows easterly for a time as a mountain stream, and finally enters the San Luis Valley about 80 miles below its source. In this valley it receives from the north the waters of the Saguache and San Luis rivers by seepage, if at all; from the west, near the lower end of the valley, the Alamosa, La Jara, Conejos, and San Antonio rivers; and from the east the Trinchera, Culebra, and Eio Costilla. About 4 miles north of the Colorado State line it enters a long canyon locally known as the Eio Grande Canyon. The general slope of the valley is still toward the south, the river descending, however, more rapidly than does the surface of the country. 12 geol., pt. 2 16 242 HYDROGRAPHY OF THE ARID REGIONS. This canyon is 300 or 400 feet deep in places, appearing from above as a gash in an otherwise level mesa. Its southern end is 3 miles below Embudo, Yew Mexico, where the walls open and the river enters the Espanola Y alley. While in the canyon above Embudo the river receives from the east Taos River, Embudo Creek, and other small streams, and in the Espanola Yalley it is increased by the Chaina flow- ing in from the west and by a number of streams from the east. At the lower end of Espanola Yalley the river passes through White Rock Canyon, a gorge in a range of hills stretching from the Jemez to the Santa Fe Mountains. From Pena Blanca near the lower end of this canyon nearly to Socorro the river flows in a valley from 1 to 3 miles wide, bounded on each side by mesas from 300 to 000 feet above the river. About 20 miles below Pena Blanca the Jemez enters from the west, and 60 miles or more below Albuquerque the Puerco comes in from the same side. Below these streams the Rio Grande has no tribu- taries of note until the Pecos is reached, about 400 miles by river below El Paso. At and below Socorro the valley contracts until it becomes too nar- row for agriculture, but from San Antonio to San Marcial the valley is from 1 to 2 miles wide. Below San Marcial the river swings to the westward around the Fra Cristobal and Caballos Mountains, which lie along the west edge of the Jornada del Muerto, the valley from San Marcial to Rincon being narrow, low, and marshy. At Rincon the river enters a canyon which extends to Fort Selden, a distance of 15 miles. The Mesilla Yalley, the most fertile valley of Yew Mexico, begins below Fort Selden and extends to the pass above El Paso, a distance of over 50 miles. Above El Paso the banks of the river again assume the can- yon like character for three miles, and the river passing this enters the Ysleta Yalley, a fine grape and fruit producing country. From this brief description of the river it will be seen that outside of the Mesilla Valley there are no large valleys 'in Yew Mexico along the Rio Grande or along any of its smaller tributaries, the valleys of the main river being generally narrow, seldom reaching a width of over two miles, and alternating with long canyons or gorges. The water of the stream, especially in the central and southern part of Yew Mexico, is heavily loaded with silt, and this is deposited to a certain extent in each of these valleys, forming broad alluvial plains. The channel of the river through these valleys is usually choked by sandbars, and in times of low water the stream divides into a number of minor channels, and apparently a large percentage of the water is lost in these great de- posits of fine material. The canyons above these valleys are not cut into hard, indurated rocks, but in many cases are bordered by steep walls of comparatively soft, friable sandstones, alternating with conglomerates or beds of clay, the whole series, in the northern part ot the territory at least, being- capped by a vesicular lava. The fall through these canyons being great, DAILY DISCHARGE OF THE ARKANSAS RIVER AT CANYON CITY, COLORADO. 1888 TO 1891. 8 January. February. March. April. May. June. July. August. September. October. November. December. 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 2 ! LIBRARY OF THE UNIVERSITY OF ILLINOIS NEWELL. J RAINFALL IN RIO GRANDE BASIN. 243 the down-cutting is rapid, and thus the waters are supplied constantly with fresh detritus, part of which is deposited in turn in the valley below. PI. lxix gives a view characteristic of these canyon walls, showing the soft crumbling sandstones and the fantastic shapes into which they are carved by the rain and frost. This view was taken near the Em biulo railroad station and in the vicinity of the point at which river gaugings had been made. The height of the cliffs from the bottom to the upper pinnacles shown in the picture is dOO or 000 feet, the total depth of the canyon at this point being about 1,000 feet. The sandstone crumbles readily under the hand, the only exception being in the case of a few thin bands, apparently containing a little lime, their superior hardness enabling them to resist erosion and thus stand out, as shown in the photograph. Such carvings of soft rock could, of course! exist only in an arid region, where the rainfall is too slight to erode rapidly or to encourage the growth of vegetation. On PI. lxviii is given a contoured map of the basin, including on the east the drainage of the Pecos and on the southwest that of the Mim- bres, although the latter river belongs to the class of lost rivers and even in times of flood does not contribute to the Rio Grande, but to the river system in Mexico west of the Rio Grande. On this map the con- tours show the elevation for each thousand feet above the sea, and the increase of height is further shown by the depth of tint, the highest mountains being heavily tinted. The great mountain ranges in the northern part of the basin, which furnish the principal supply of water, are thus clearly shown, and on the south the broad desert plains are seen, together with their relation to the river and to the dividing ridges of mountains. This map is of necessity generalized to a large extent, from the fact that topographic surveys have not been carried on over a large part of the area. ANNUAL AND MONTHLY RAINFALL. The annual rainfall, as measured in various parts of the Rio Grande basin, is shown graphically on Fig. 223, the stations selected being those in or near the basin and for which there was the longest record. Ten stations are represented on this diagram, the depth of rain at each being shown by the height of the black blocks or steps above each base line. Each year during which observations were made is represented by one of these blocks or steps, the blank spaces showing either that no observations were taken or else that they were not continuous throughout the year. The horizontal lines give the depth in inches and the vertical lines divide the five-year periods, so that wherever the observations are complete there are five of these black steps or blocks between two vertical lines. The years are shown by the figures at the top of the diagram, 1860-1864 signifying that the observations on these years whenever made are to be found in that space. Most of the obser- 244 HYDROGRAPHY OF THE ARID REGIONS. rations, however, begin about 1870 and continue with more or less in- terruption until 1889. This diagram serves to show the great irregularity in the measured rainfall and the range in total depth for any one place, and demonstrates how difficult it is to draw general conclusions. The most marked fea- ture is the extraordinary rainfall reported at Fort Garland in the years 1870, 1871, and 1872. It is highly probable, however, that this report is an error, although the individual observations of the storms in these years do not seem to indicate it. In the lower left-hand corner the rain- fall at two widely separated stations is given, that for Fort Selden for the years 1867 to 1876, inclusive, and that for Dealing from 1883, con- tinuing through that decade. cO cD cO co S fff'k 1 r aeo 5 H4HMS tSONS UJHPU'U LIBRARY OF THE UNIVERSITY OF ILLINOIS NEWELL.] THE RIO GRANDE IN COLORADO. 245 southern part of the basin, however, the rainfall apparently fluctuates for the most part below 10 inches a year, at long intervals rising above this. The distribution of the rain by months throughout the year at various stations in the Rio Grande basin is shown on PI. lxx, the height of the small black pillars showing the mean depth of rainfall at the various stations named for a period of from 12 to 15 years. This diagram does not exhibit the rainfall in any one year, but shows the average distri- bution at these points. The most noticeable feature is the excessive rainfall at all stations in July, and especially in August, and the di- minished amount in the early and late months of the year. The basin of the Rio Grande can readily be divided into a number of parts, belonging to one or another of the three classes of drainage dis- tricts — headwaters, trunk-stream, or lost rivers. These are usually sharply distinguished by peculiar topographic features, and are well recognized in common usage. In the descriptions of the hydrography of these, given in the following pages, the order of succession is taken in general from the headwaters down, taking first the district in the State of Colorado, including the source of the river, the San Luis Park and the lost river basins to the north, then the Taos district and the adjoining areas, and in succession the Espanola Valley, the Chama dis- trict, the Santa Fe district, the Albuquerque Valley, the tributaries below the Chama, and the Mesilla Valley. After these descriptions of the main Rio Grande drainage, that of the Pecos in New Mexico is given, condensed from a report by R. S. Tarr, and finally the lost river basins between the Rio Grande and Pecos are briefly mentioned. THE COLORADO DISTRICT OF THE RIO GRANDE. The headwater district of the Rio Grande Basin, embracing the San Luis Valley, surpasses all other subdivisions in extent of irrigation and permanence of water supply, and is of the first importance in any con- sideration of the conservation of the waters. The general elevation of the cultivated land of this division is from 7,500 to 7,700 feet or over. The central plain is bounded by high mountains of 9,000 to over 13,000 feet in elevation on all sides, excepting on the south, where the valley opens into New Mexico. The southern boundary of this district may be taken as coincident with the State line of Colorado, for on the south the topographic features do not sharply divide this district from the adjoining portions of the Rio Grande Basin. The great division of the river basin includes 45 square miles in San Juan County, 615 square miles in Hinsdale County, 2,520 square miles in Saguache County, 1,170 square miles in Rio Grande County, and all of Costilla County — 1,720 square miles, and of Conejos County 1,200 square miles — in all an area of 7,270 square miles. The total area of the comparatively level lands of the valley is 2,400 square miles, and of the high mountains4, 870 square miles. Most, if not all, of the water must 246 HYDROGRAPHY OF THE ARID REGIONS. be derived from this latter area, namely, of these higher mountains, for the rain which falls upon the valley itself does not add perceptibly to the available supply of water. From the high mountains which surround this division come innu- merable small streams, some of which unite into creeks of notable size, while others sink, gradually disappearing into the porous soil of the valley bottom. The Rio Grande rises in the extreme western prolonga- tion of this drainage area, and flows in a general easterly course, re- ceiving a number of these small streams on its way. Shortly after en- tering the valley proper, or park, as it is sometimes called, near the town of Del Norte, it begins to take a general southwesterly course, which finally changes to the south. Beyond .Del Norte are few streams contributing water to the river throughout the year: so that, taking the year as a whole, the maximum amount of water in the river is to be found comparatively near the head of the river, and probably not far from Del Norte. In its headwaters the Rio Grande is a torrential stream, but after leaving Wagon Wheel Gap it gradually loses its steep descent, and ♦ beyond Del Norte has a very light grade, becomes sinuous, and often divides into several channels, especially in floods. There is constant tendency to shift the channel and to cut off the loops, and thus great trouble and expense are occasioned to the owners of canals, in the at- tempt to preserve the headworks and prevent the river from washing them out or leaving them. The gauging station of the Geological Survey is at a point about 3 miles above Del Norte, thus obtaining the discharge of the river above the headworks of most of the canals, so that the measurements given in the accompanying tables may be taken as showing the maximum flow of the river at the point between the torrential portion and the sinuous plain portion. The discharge for nearly two years is shown on PI. lxxi, by the examination of which the relation between the floods of 1890 and 1891 can be seen at a glance. In 1891 during the early months the water was high, and there was promise of a large flood. This culmi- nated, however, in the first week in May, and then declined rapidly, reach- ing its lowest point at the time when on the previous year the water was highest. The dotted line in July, August, and September gives the approximate discharge for 1889, the measured discharge for the rest of that year being shown by the fine line. The greater portion of the catchment area of this division does not contribute water to the Rio Grande; thus there are two subdivisions — that of the perennial drainage of the Rio Grande and the lost river drainage. The entire northern or northeastern part of this division in Colorado belongs to the class of lost rivers, since the waters of the streams do not penetrate across the broad San Luis Park, but gradu- ally disappear into the gravelly soil — as, for example, the Saguache Creek — or flow into the San Luis lakes, from which they escape by evaporation, leaving the bed dry for a part of the year. EARTH COLUMNS AT EMBUDO, NEW MEXICO. LIBRARY OF THE UNIVERSITY OF ILLINOIS . NEWELL.] AGRICULTURE IN SAN LUIS VALLEY. 247 Although a large per cent of the drainage from the mountains sur- rounding the park is lost by evaporation, a small amount penetrates the soil and fills the porous strata. The extensive irrigation which, is practiced in the central parts of the plain also adds water, and thus the unconsolidated sands and gravels are completely saturated. These waters gradually rising in the earth tend to create swamps, and al- ready certain areas of valuable land have been ruined. Systems of drainage must be constructed in many places to take away this injuri- ous excess of water. It has been found possible to recover some of this water by means of wells, and on the lower grounds a large number ot artesian wells of small diameter and of depth from 70 to 200 feet or more have been put down, giving an excellent supply for domestic purposes and for watering stock. SAN I. CIS VALLEY. The San Luis Park or valley proper comprises the lower lands or central part of the basin, and consists of the broad extent of nearly level land, the soil being probably of lacustrine origin. Large irrigat- ing systems take water from the Rio Grande and carry it both north and south into these rich and level bottom lands, while smaller canals and ditches owned by farmers are to be found around the edge of the valley, utilizing the water of the smaller streams. This valley is far the largest -on the Rio Grande, being nearly 70 miles long and 40 miles wide, the vast extent of unbroken land sur- passing in area the total of the agricultural land along the river in New Mexico. The surface slopes from both sides away from the river, the stream flowing upon a low, broad ridge and the valley bottom as a whole falls gently toward the south, parallel to the river. Although the altitude of the lands of the valley bottom is high, yet the climate is not too severe for agriculture. The snowfall is generally too light to insure the success of winter wheat, and disappears rapidly toward spring. The soil of the valley varies greatly, some of it being a sandy adobe, and in other places a coarse gravel. There is often a sandy loam from ^ gc b 7 ^ J ■S k ^ ^ 5 ^ >5 o: k \ vj k o O ly *0 O ^ Q 5 inches 4 inches. 3 inches. 2 inches. 1 inch. Fort Wingate. Elevation, 0,822 feet. Fort Union. Elevation, 0,750 feet. Fort Stanton. Elevation, 0,150 feet. Fort Selden. Elevation, 4,250 feet. 5 inches. 4 inches. 3 inches. 2 inches. 1 inch. 5 inches. 4 inches. 3 inches. 2 inches. 1 inch. 5 inches. 4 inches. 3 inches. 2 inches. 1 inch. 5 inches. 4 inches. 3 inches. 2 incites. 1 inch. AVERAGE MONTHLY RAINFALL AT STATIONS IN THE RIO GRANDE BASIN IN NEW MEXICO. library OF THE UNIVERSITY OF ILLINOIS NEWELL.] IRRIGATION IN SAN LUIS VALLEY. 249 Irrigation for grass and meadow lands begins about tlie 1st of May, and for grain and potatoes about a month later. After the hay is cut the ground is often given a second watering for aftermath. On meadow land three good floodings are required, except on the bottom or lowlands, where two are used. For grain there are three waterings on higher land and two on the lower land. Irrigation ends for grain and potatoes from the first to the middle of August. In general, the larger canals in this valley are very wide and shal- low, and are built for a considerable portion of their way in embank- ments raised slightly above the general level of the surrounding ground, allowing the water to be easily conducted out upon the fields. The loss by evaporation and seepage at such places is in consequence very great. The advantage, however, of this method of construction is that the cost of a shallow canal is usually less than of one having a deep cross sec- tion, and the banks are less liable to be destroyed. Wherever practi- cable, however, the canals have been partly in excavation and partly in embankment. Almost without exception the head works of the canals, including gates, dams, flood weirs, etc., are constructed of wood, and are of a very temporary character. There are few boxes or devices employed in the valley for the absolute measurement of water, since the canal companies have not felt the necessity of accurately measuring the amount of water given to the consumer. With the increase of the number of canals and in sale of the water rights there is a prospect, however, of the general adoption of some form of measuring box or weir which measures water in statutory units. The San Luis Valley comprises eight of the water districts of the State of Colorado, these districts being Nos. 20 to 27, inclusive. The administration of the water service of the canals lying in these dis- tricts is subject to the control of the water commissioners. The rules governing the service of the canals are enacted by the companies own- ing them. Many of the canals were built by irrigators, but the largest, as for example the Citizens’, Del Norte, Empire, and San Luis canals, were constructed for the purpose of selling and renting water. They usually rent water for a term of from one to live years, the lessee sign- ing an agreement binding himself to use the water for his own purposes only, not to let any of it run to waste, and to fulfill other requirements. Some of the companies agree that whenever, through scarcity of water, due to neglect, they can not deliver the amount called for in the agreement, they will pay the damage caused thereby to the irrigator. The amount charged for the rental of water has been fixed by the com- panies, and generally varies from year to year. With the Citizens’ and Del Norte canals the prices have ranged from 80 cents to $1 per statu- tory inch per year. The farmers seem to prefer to pay a dollar or even more per statutory inch each year for the rental of water rather than buy a perpetual right 250 HYDROGRAPHY OF THE ARID REGIONS. or agreement to irrigate perpetually a certain area of land. This is caused by poverty, by doubts as to the perpetuity of the right, or by fears that the company furnishing water will sell more than it is able to supply. The perpetual use of 1 inch of water has been sold for from $5 to $8, and in one case perpetual water rights for 160 acres sold for from $800 to $1,000, the rights in this case being considered to be the perpetual use of 2*88 cubic feet per second through the irrigating season. These rights are subject to an assessment each year, which the companies agree shall not exceed a specified amount, and it is further agreed by certain companies that, when three-fourtlis of the capacity of the canal has been sold, the management of it shall be placed in the hands of the water-users. The duty of water in this valley has been a matter of considerable attention, but the results obtained have not been wholly satisfactory, on account of the fact that there were no devices in general use for the ab- solute measurement of water. In a small portion of the valley there is considered to be what is commonly known as a “ standard” duty of water, viz: 1-44 cubic feet per second to 86 acres, or 1 cubic foot per second to 55 -5 acres. The farmers taking water from the Del jSorte and Citizens’ canals buy or rent it on the basis of from 4 to 1 statute inch for each acre. This latter figure gives the extremely low duty of only 35 or 40 acres per cubic foot. In fact, the duty of water varies very widely, ou account of the differ- ences in the character of the soil, kind of crop, the length of time the land has been irrigated, and the intelligence of the irrigator. The seep- age of water through different soils is so widely different that the irri- gator can not in many cases estimate what portion of the water passing through the headgate on his lateral really reaches the field. To illus- trate the difference of opinion or of practice, it may be well to cite the case of a manager of one of the great farms of the valley, who asserted that certain tracts required thirteen floodings, while others required only one, or possibly two, to produce the same result. A few farmers who have been, perhaps, more careful in the use of water, and have considered the subject thoroughly, believe that 1 statu- tory inch is ample for 2 acres, and state that experience has shown that 80 inches of water purchased from a canal has not only watered 160 acres, but that there has been a surplus for use on other ground. Some of the canal companies in selling water by the acre calculate at the rate of § of a miner’s inch to the acre, or a duty of about 60 acres to the second- foot. There is no doubt as to the increased duty of water from one year to another; everywhere this question, when asked, has been answered in the affirmative, and it was often stated that during the second year of cultivation the land required only about three-fourths as much water as during the first year. The duty continues to increase, but not as rapidly as at first, until the limit is reached, every portion of the ground DAILY DISCHARGE OF THE RIO GRANDE AT DEL NORTE, COLORADO. TWELFTH ANNUAL REPORT PL. LXXI LIBRMW 0,5 NEWELL.] TOPOGRAPHY OF TAOS VALLEY. 251 being thoroughly soaked. The results of this are easily observed, for in tracts of land that have been irrigated continuously for a number of years, the low portions of the held have turned into swamp. On land that has been irrigated for four years, it is asserted that on the fifth year a crop can easily be raised without any irrigation, except that from the seepage from the ditches. THE TAOS DISTRICT OF THE RIO GRANDE. South of the Colorado district, and immediately adjoining it, on the east side of the river, is a portion of the Rio Grande Basin, which may be called for convenience the Taos District, from the name of its prin- cipal valley. Tliis division includes the streams flowing westerly from the group of mountains of which the Taos Range is of chief importance. The topography of this division is peculiar, and distinguishes it sharply from that of the San Luis Park to the north. The surface rocks con- sist largely of soft clays, sandstones, and gravels, underlaid by a broad sheet of lava, which appears on the sides of the canyons along the Rio Grande and its tributaries. These easily eroded deposits are deeply cut by occasional storms, and loose material is carried by every flood to the Rio Grande, causing its waters to be turbid and at times overloaded. The streams leaving their mountain canyons flow for a time over this lava sheet with gentle current, depositing much of the' material brought down from the heights and forming alluvial plains; then, as they ap- proach the Rio Grande, they reach the point where the lava has been worn away, and with swift current flow rapidly downward into narrow canyons to join the main river. The principal valleys in this division from north to south are the Cerros, Rio Colorado, San Cristobal, Arroyo Hondo, and Taos, which will be described in turn from north to south. At Cerros there is no distinct valley or stream, but several small streams, viz, the Latir, Rito Priiuero, and Rite del Medio, are taken by ditches and brought into one channel, being caught just after they emerge from the Cerros Mountains. The combined flow does not exceed 20 second-feet. The amount of irrigable land is largely in excess of the present water supply, for a strip extending from the mountains to the Rio Grande, a width of some 8 miles and running parallel to the river for at least 15 miles, can easily be brought under ditch. The land to which water has been brought is scattered and irregular in outline, but there are estimated to be in all about 960 acres under ditch, and nearly all of this is farmed to a certain extent. By a proper system of stor- age, such as is possible on these mountain streams, the greater part of all this area might be brought under cultivation. The first valley south of the Cerros region is that through which Col- orado Creek flows. This valley is about 4 miles long and contains,- it is estimated, about 1,800 acres adapted to irrigation, fully 1,500 acres of this land being under ditch; only a portion, however, is annually under 252 HYDROGRAPHY OF THE ARID REGIONS. crop. The water supply is derived from two forks of the stream, which join above the place at which water is taken out. It is estimated that nearly half of the water of Colorado Creek is taken across a divide and carried to the mines at Elizabethtown. In the valley the stream was flowing at the rate of 23 second-feet early in March, 1889. South of Colorado Creek and between it and the Arroyo Hondo is a tract of land 8 to 10 miles wide, extending from the mountains to the Eio Grande. The greater portion of this is covered with timber, heavy among the foothills but growing thinner away from the mountains. Several small creeks whose waters are used in irrigation cross this tract, the largest of these being the San Cristobal, the waters of which are used in a small valley containing about 1,800 acres of land. This is the smallest and least important of the valleys between the Eio Grande and the Taos Mountains, being occupied by a few ranches. The bench portion of the San Cristobal Valley, containing in all about 800 acres, may be considered as irrigable land; of this about 400 acres are under ditch, and the rest could be easily watered. Hot more than 250 acres are actually tilled or used as hay fields. The stream is very small, and does not exceed 8 second-feet at ordinary stages, so that it is doubtful if more could be done with the present water supply. The Arroyo Hondo is the next stream in order south of the San Cristobal. The valley through which it flows is from one-half to three- quarters of a mile wide for the distance of about 4 miles, then it contracts and again opens at short intervals. This valley is for the greater part of its course fully 500 feet below the general level of the surrounding country. The two main ditches which furnish water for the tilled land are taken out about one-half mile up in the canyon on opposite sides of the river. This stream, as measured on February 26, 1889, above these ditches, was flowing at the rate of 17 second-feet, and on November 5, 1890, at about 13 second-feet at a point below Frasier’s Mill. The land in the valley, in all from 1,200 to 1,500 acres, not including the gorge at its upper or the canyon at its lower end, maybe classed as irrigable. The main ditches being taken out, one on each side, nearly all the land may be said to be under ditch. A great portion of this area is in crop, and yet it is claimed that but little over one-fourth of the total water supply is used. South of the Arroyo Hondo is the principal valley of this division — the Taos Valley — surpassing all the others in water facilities and area of crops cultivated. The term “Taos Valley” is apt to give a false im- pression, for the true valley of the Taos Creek is but a shallow and rather narrow cut in the lava extending from the west side of the Eio Grande nearly to the mountains. The name is given, however, to the lava mesa, about 12 miles long from north to south and about 8 miles wide, lying between the Eio Grande and Taos Eange and having a large population, mostly Mexican. Water for irrigation is obtained DAILY DISCHARGE OF THE RIO GRANDE AT EMBUDO, NEW MEXICO. January. February. March. April. May. June. July. August. September. October. November. December. 10 15 SO 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 2i library OF THE RSlTY OF ILLINOIS NEWELL.] WATER SUPPLY OF TAOS VALLEY. 253 from Taos Creek anil its branches, and from the Arroyo Hondo and Seco. The altitude, nearly 7,000 feet, is too high for many kinds of fruit, but large quantities of grain are raised. The amount of land in the Taos Valley upon which water could be brought is very large, certainly as much as 50,000 acres, and probably even more. The most reliable information indicates about 15,000 acres actually under ditch. This acreage is difficult to estimate, as the land lies in very irregular patches, often isolated, and having an irregular frontage on a stream or ditch. On account of scarcity of water not more than one-thiril of the land under ditch is annually tilled, the sta- tistics for the census year 1889 showing 5,500 acres of crops raised by irrigation. The Taos Range to the east is well timbered with pine and spruce, and contains deposits of gold, silver, and other minerals, which are worked in a small way, development of mining industries, however, being retarded by the lack of shipping facilities. The rainfall in the valley is estimated to be about 16 inches, the greater portion falling during August. There is no economy of water, large amounts being wasted on account of the numbers of small ditches running parallel with each other and taking the water from the river in the most wasteful manner. In place of two good high-line ditches, one on each side of the creek, so built as to carry the entire summer flow of the stream, there are several small acequias built by the early Mexican settlers in such a way as apparently to meander through the land without any system or definite order. Three principal streams belong to the Taos Creek system, and in fact form the Taos Creek, as this name is given only to the resulting stream. Their names are Pueblo Creek, Ferdinand, and Rio Grande de Taos. From gaugings made by the hydrographers of this Survey below the junction of these creeks it appears that their winter flow does not exceed 50 second-feet. This amount is increased in the spring by melting snow, but it is doubtful if there is more water during summer irrigation, and it is even probable that at that time the supply is usually less. During the last ten years two droughts are reported to have occurred, and it is asserted that the Taos Valley for the last fifteen or twenty years has been subject to periodic droughts at intervals of about three years. Pueblo Creek on the north enters the valley a short distance above the ancient Indian pueblo of Taos. The Indians residing here have taken out two acequias above their pueblo, one on each side of the creek. The largest ditch taken from this creek has a bottom width of 4 feet, anil runs towards the town of Taos, its surplus water finally emptying into Taos Creek. Pueblo Creek carried on February 27, 1889, about 13 second-feet. Its regular summer flow is not entirely utilized. Lucero Creek is a tributary to Pueblo Creek, coming in from the north or right-hand side, and watering the land lying between it and the Pueblo Creek, as well as a tract of land extending 2 miles to the north of the 254 HYDROGRAPHY OP THE ARID REGIONS. creek. The Seco is another tributary of Pueblo Creek, its waters, how- ever, being taken out entirely during the irrigating season, so these waters do not at that time reach Pueblo Creek. Between the Lucero and the Seco is a large tract of land that could be brought under culti- vation by high-line ditches taking water from tributaries of the Arroyo Hondo, Lucero, and the Pueblo Creeks. Ferdinand Creek issues from a narrow canyon about 3£ miles above Taos, where three or four small ditches or acequias are taken from it. The discharge of this stream on February 27, 1889, was only 3 second- feet; its summer flow was reported, however, to be considerably larger. Several years ago, during a dry season, the irrigators having land de- pendent upon this creek constructed a small reservoir at a favorable point several miles up the canyon, but the embankment was washed out before the end of that year. The Rio Grande de Taos, which lies furthest to the south, has one tributary, known as the Rio Chiquito, which joins it 2 miles below the point where it enters the valley. Two small ditches are taken from this latter, while from the Rio Grande de Taos ten or more are taken out at short intervals from each other. During the summer season, when the farmers are using the water, there is little, if any, left flow- ing in the stream. The Rio Grande de Taos on February 23, 1889, car- ried 17 second-feet below its junction with the Rio Chiquito. By storage in the headwaters of this creek a large tract of land could be irrigated, an amount depending mainly upon the capacity of the reser- voir. Below Cordova the Taos River flows through a canyon to join the Rio Grande. Along its course below the town one or two acequias are taken out, but a large portion of the water is not utilized. The popu- lation of the valley is about 7,000, principally Mexicans and Pueblo Indians, these latter owning a tract of land a Spanish league square. They are peaceable and industrious, making better agriculturists ap- parently than their Mexican neighbors. Wheat, corn, oats, barley, beaus, potatoes, pumpkins, and other vegetables are raised in the valley, and recently apple trees have been planted with success. Alfalfa can be cut three times a year, averaging 1£ tons per acre at each cutting. The shipping facilities to and from this valley are very poor, the nearest railroad station, Embudo, being about 30 miles away. Wheat is the most important crop grown in this valley, and flouring mills have been built at the Ranchos de Taos. Before the present rail- ways were constructed Taos was an important flour -producing center for the surrounding towns, and even at present flour is sent by wagon or pack train to local mining camps or to be reshipped by railroad. The Mexican system of threshing, that of treading out the wheat by goats or other animals, has led the Americans and better class of Mex- icans to use other flour even when it is more expensive. An objection NEWELL.] IRRIGATION METHODS IN TAOS VALLEY. 255 to this mode of threshing is that the wheat when gathered from the ground contains pebbles about the size of the grains. It is impossible to separate these pebbles from the wheat by winnowing on account of their weight, and they are consequently ground with the wheat, making the flour somewhat gritty. Oats rank next to wheat in importance, and yield large crops. Beans and peas come next, while corn is but little grown, and then almost entirely by the Indians. Of late years the bean crop has been much damaged by the attacks of insects, amount- ing at times even to the loss of the crop. Irrigation by flooding is the system practiced throughout the Taos val- ley. In each field, after plowing and smoothing, small banks of earth are thrown up with the plow or spade, dividing the field into a number of rec- tangular divisions called squares. To irrigate this land a small opening is made in the main ditch, or lateral, as the case may be, and water is allowed to flow into the first division or square, from which are openings into the next square, and so on, the water flowing from square to square over a large portion of the field. “Banking” is but a variation of the flooding system, the water being retained as long as thought necessary in one square before it is allowed to flow into the next. The advocates of this system claim that by checking the flow in this manner the silt is deposited evenly over the whole surface, while by the former method it can be deposited only in more favorable places. The land is also more thoroughly soaked with water, and better results are therefore claimed. There is a con- stantly increasing use of fertilizers, such as corral scrapings and barn- yard manure, and better results are obtained after their use. Each community in New Mexico has its own customs, many of these dating as far back as the second conquest by the Spaniards. Thus, iu communities often but a few miles apart, there is considerable difference in the details of water administration. Taos has the major-domo system, which prevails, with various modifications, throughout New Mexico. Every spring one of the irrigators is elected by popular vote to the position of major-domo. His powers are wide and varied; he not only acts judicially, but he has power to see that his decisions are obeyed. The ditch is regarded as common property of all who hold land along it. In the early spring every man who takes water from the ditch meets the major-domo at the tail of the ditch and is assigned to his task by the major-domo, who measures off the sections and assigns them at random. A man is required to clean, repair, and put his section in perfect order, the major-domo alone being exempt from ditch work, but receiving no salary. The distribution and assignment of water is entirely in the hands of the major-domo. The water is given to each irrigator for a certain period, and the decision rests entirely with the major-domo as to the length of time during which he shall have the use of the water. There 256 HYDROGRAPHY OF THE ARID REGIONS. is no apparent rule as to the necessity of employing the water to best advantage, the only requirement being that no irrigator shall overrun the time allotted to him. There are complaints from both Americans and Mexicans of partiality shown by the major-domo, and it is easy to conceive into how demoralized a condition a corrupt major-domo might bring a community, especially in times of scarcity of water. The Mexicans in the Taos Yalley and the Indians are reported to have an agreement, dating as far back as the second conquest, by the terms of which the Indians were to have full and exclusive use of the water of Pueblo Creek for four days in the week. The Indians also allowed certain Mexican settlers on the Arroyo Seco to take from the Lucero, a tributary of Pueblo Creek, as much water as would flow through an old-fashioned cart or “ car r eta” wheel. Both of these rules are said to be observed even at the present time. Summary of land. Locality. Irrigable. Under ditch. Cropped in 1889. Acres. 100, 000 Acres. 960 Acres. 540 1,800 800 1,500 400 800 160 1,500 65, 000 1, 200 15, 000 600 4,000 Total 169, 100 19, 060 6, 100 In the case of irrigable land the figures are probably much too small iu the cases of Taos and Cerros. The water supply is comparatively small, and the amount of land is so vastly in excess of the available water that it is not a matter of great importance. TRES PIEDRAS MESA. The Tres Piedras Mesa may be taken as including all the country west of the Rio Grande and opposite the Taos Valley, extending from San Antonio Creek ou the north to the Black Mesa, just above Es- panola, on the south. This vast extent of practically level land is nearly all underlaid with lava. There are several townships of good land on top of the lava, but water could be brought to it only at great expense, as a ditch from the Alamosa or San Antonio River must pass through lava rock for a great part of its length. The Taos Yalley Ditch Com- pany was organized to reclaim this land, but their work is now ap- parently at a standstill, they having built a ditch about 40 feet wide from the Alamosa to the San Antonio, dammed the latter stream just south of Antonito, and taken out a ditch 40 feet wide from it. In May, 1889, this ditch was carrying some 500 second-feet to the end of the excavation, when the water was allowed to escape and to find its way into the Rio Grande Canyon the best it could. NEWELL.] SEDIMENT MEASUREMENTS AT EMBUDO. 257 EMBUDO ^GAUGING STATION. % In the lower end of the canyon, between the Tres Piedras Mesa and the Taos Valley, is the Embudo gauging station of the Geological Sur- vey, located at that point for the purpose of obtaining the total dis- charge of the river below the Colorado divisions and above the Espanola Valley. The results of the measurements at this point are shown on the tabulations appended, and also on the diagram, PI. lxxii. This shows a progressive increase in the amount of water from 1880 to 1891, the spring of the latter year being marked by a large flood of short duration. This flood can also be seen on the diagram, PI. uxxi, for the Del Norte station, shown there a few days earlier and far less in amount. At Del Norte the spring flood of 1891 did not reach the maximum of the preceding year, but at Embudo it far overtops that of 1890. Observations of the amount of sediment, as described in the pre- vious annual reports, were carried on for a time at Embudo, and the results are shown graphically on Fig. 224, giving the observations from January 14 to April 15, 1889. In the upper part of this diagram the irregular line shows the fluctuations in the height of water, due proba- bly to changes of temperature. The observations during January and February were made a number of times a day with great care in order to show this constant fluctuation of the height of the stream. In March and April, however, they were made only twice a day, so that the diurnal variations do not appear. Thelower part of the diagram shows the proportion of sediment in the water on those days. The dotted line connects the mean observations of samples of water taken from near the bottom of the stream, the ob- servations themselves being shown by the small circles. The results of the sediment determinations made from samples of water taken near the surface are shown by the small crosses, the solid line connecting the mean of these whenever more than one was taken at a time. The dia- gram exhibits the wide range of results obtained from samples taken at the same point, at the same time, and under circumstances precisely identical. This is especially noticeable when the stream is laden with silt, check samples at that time differing greatly in the percentage of solid matter. This lack of agreement among samples taken at times when the river is' loaded with sediment is rather to be expected, from the fact that the water is moving with that peculiar boiling motion characteristic of floods, and, as can be seen by the difference in color of the water, all parts are not equally loaded. The diagram also shows that on the approach of the spring floods the proportion of sediment increases, but drops off rap- idly, either by dilution or by exhaustion of the supply of fine material accumulated during periods of low water and sluggish flow. The diagram shows the proportion of sediment by means of two scales, that of grammes per cubic foot, as given by the horizontal lines, and of 12 geol., pt. 2 17 Parts by rretyhjt in loo.ooo. 258 HYDROGRAPHY OF THE ARID REGIONS parts by weight in one hundred thousand shown by figures on each edge of the diagram. During April the proportion of sediment in the surface samples, as shown by the small crosses, increases to such an ex- tent that this part of the diagram overlaps that showing the height of water. This diagram can be compared with that for sediment at El I aso, given on PI. lxxiv of the last annual report. The greater amount of sediment at that latter point is shown by the fact that in the Embudo diagram the height only allows representation of 65 parts of sediment by weight in 100,000, while the smallest division of the El Paso diagram gives 100 parts in 100,000. JAN FEB MARCH. APL. Fig. 224. — Diagram illustrating sediment measurements at Embudo, New Mexico. ESPANOLA VALLEY. South of the Taos district and the Tres Piedras mesa is a large val- ley lying along the Rio Grande and containing an area of agricultural land so great that it may be said to constitute a separate trunk-stream division of the Rio Grande system, known as the Espanola Valley. Before entering the valley the Rio Grande flows through a canyon rrtxght. in. loo.ooo. NEWELL.] ESPANOLA VALLEY. 259 whose walls rise somewhat abruptly to the height of 800 to 1,000 feet. Throughout this distance the river is of a torrential character and the process of down cutting is still active. Owing to the general rocky character of the river’s bed, this portion of the river is suited for the construction of headworks for a canal, which would become a high-line ditch farther down. About three miles below Embudo Station the canyon walls retreat abruptly, especially on the west side, giving room for a border of irreg- ular hills between the higher mesa walls and the flood plain adjacent to the river. This is the beginning of the Espanola Valley, which ex- tends to White Rock Canyon, about 25 miles or more below. About two and one-lialf miles below Embudo railroad station the first acequia, of capacity of about 10 second-feet, is taken out on the east side of the river. To divert the water into it a rude dam of stones and brush has been constructed by the Mexican farmers living at La Joya. The river assumes a different character on emerging from the can- yon, the velocity being diminished and sediment deposited, forming a sandy channel and shifting banks. In this portion of the river head- works of canals can be maintained with difficulty owing to the insta- bility of the foundations. About three-quarters of a mile below the mouth of the canyon is the Mexican village of La Joya, which stretches irregularly along the road for nearly a mile. Almost all of the low- lying land is under ditch and cultivation, as is the general rule through- out the Espanola Valley wherever the land is of good quality. The manner of applying water to the soil is very simple. The land is laid off in squares, and the water drawn on them in most cases directly from the main ditch, though in some cases short laterals at right angles to the main ditch are used. Several thrifty orchards of apple and peach trees are to be seen at La Joya, but they were small in extent, generally not more than one-third of an acre. From the mouth of the canyon to La Joya church there is scarcely any land that could be brought under cultivation by a high-line ditch, but below the church is a small plateau or bench, about 75 feet above the river, which might be brought under ditch, although much grading would be required in preparing the land for the water. About 3 miles below La Joya is San Juan, an Indian pueblo, the thrift and prosperity of which, as exhibited by the fields and adobe houses, is notable. From San Juan to Espanola the lowlands are under ditch, and in the main are cultivated, but the soil appears poorer or the cultivation worse than at San Juan, and there are a few deserted houses. In the valley, as a whole, the land is irrigated only upon the lowest level, and a large tract on the east side of the river near La Joya and Alcalde, although smooth and admirably adapted for irriga- tion, is unused. A high-line ditch was projected, to be taken out of the river below Embudo railroad station, which was to take in this land and run as far south as the mesa beyond Santa Fe Creek. The men inter- 260 HYDROGRAPHY OF THE ARID REGIONS. ested in the scheme are reputed to have obtained a small sum of money and then left without accomplishing anything in the way of construc- tion. Not more than one-third of the irrigable land in this portion of the valley is actually under ditch. About 5 miles above the town of Espanola the Chama River enters the Rio Grande, the muddy water brought by this stream changing the character of the river deposits. Above the junction these are sandy, but below the Chama they are of a more clayey nature and in several places the river has divided into two or more channels. Just below Espanola the Santa Cruz Creek enters the river from the east, discharging in March, 1889, about 15-second feet, but carrying a larger quantity 2 miles above Santa Cruz pueblo and the Mesilla acequia. This acequia runs about 5 miles down the Espanola Valley to and past the village of Mesilla. Just below Mesilla are the remains of a very large ditch, which was dug about forty years ago. It extended from below Espanola to below the Huerfano Butte, a distance of from 8 to 10 miles. The owner ap- parently abandoned it, and the headworks were soon washed away, so that for many years there has been no water in the ditch. From the Huerfano Butte to San Ildefonso Pueblo, a distance of about three- quarters of a mile, is little or no irrigation, and no very readily irri- gable land, though there are traces of old ditches, probably the end of the old ditch mentioned above. At San Ildefonso, in the southern end of the Espanola Valley, the waters of Pojuaque Creek are used for irrigating several hundred acres, as well as for lands along this creek as far up as the village of Pojuaque. The stream was flowing about 20 second feet when measured in March, 1889. The San Ildefonso Indians have a large body of land under cul- tivation between their pueblo, the river, and White Rock Canyon, all of which is served by Pojuaque water. Only a small portion, perhaps 10 per cent, of the water of the Rio Grande is taken out in the Espanola Valley, and much of the irrigation of the valley is done with water from the creeks which flow into the river from both sides. The use of this water in preference to that of the Rio Grande is due to the greater ease with which it can be brought •on the land and to the difficulty of constructing and maintaining head- works on the river. The population of the valley is almost entirely Mexican and Indian, and, while nearly all of the easily irrigable low-lying lands are under irrigation, it is apparent that the productiveness could be much in- creased by better cultivation, with improved farming implements and better management. The Indians cultivate only enough land to supply their needs, and thus have large areas of fertile lands untilled. The ditches are all small and are owned and maintained by the various communities. The lands of this valley as a rule have a little alkali, but not enough to seriously interfere with agriculture. There appeared NEWELL.] TOPOGRAPHY OF CHAMA DISTRICT. 261 to be a greater proportion around San Ildefonso than elsewhere, but even there it seemed to be no serious obstacle. The eastern limit of practicable irrigation in the valley is marked by “bad lands,” which consist of beds of gravel, sands, -and clays, sculp- tured into fantastic forms by erosion similar to those shown in PI. lxix. The country is barren and sandy until the divide that separates the Espanola Valley proper from the Pojuaque Valley is crossed. The Pojuaque Valley is narrow, and the amount of water in the stream small, the present settlers requiring for their use all the water avail- able. The stream flows for a great part of its course in a canyon that extends to the mountains, a few miles above Pojuaque Pueblo. A short distance below Pojuaque the Tesuque joins the Pojuaque, the resultant stream flowing through a valley about eight miles long before reaching the Rio Grande. The Tesuque is about the same size as or a trifle smaller than the Pojuaque. The irrigable land consists of a narrow strip on each side of the stream, averaging about half a mile in width. It is doubtful if more land than at present tilled can be irrigated during dry seasons by the present unregulated supply. A high barren divide, with cedar and piiion bushes, separates the head- waters of the Tesuque from those of Santa Fe Creek to the south. THE CHAMA DISTRICT. The Chama, 1 which, joins the Rio Grande in the Espanola Valley, is perhaps the largest tributary of that river, draining an area of 2,300 square miles, or nearly one-quarter of the total catchment area of the Rio Grande above the junction of these streams. This drainage basin consists principally of high plateaus and mountain ranges, and there are no alluvial valleys, strictly speaking, except a long, narrow valley below Abiquiu. There are, however, several low, fertile mesas, which are as valuable as valleys. The richest one is between the Nutrias and Brazos rivers, in the Tierra Amarilla grant, this tract containing also several other tine low mesas. Little, however, has been done to develop this great area, although its possibilities are large. From Chamita, at its mouth, to Abiquiu, some 25 miles above, the Chama flows in a valley similiar to that of the Rio Grande, but with somewhat greater fall. The lower part of the river’s course is through a broad valley; above this are canyons, and again a broad valley, this latter being below the canyon in the Tierra Amarilla Mountains. There are thus four general divisions, an upper and a lower valley, witli a long canyon above each. The lower Chama Valley is bordered by broken hills and bluffs of soft sandstone, similar to those shown on PI. lxix, clay and gravel, and ‘the higher mesa, capped with lava, seldom approaches the river. Above Abiquiu the canyon portion, called the Canyones de Chama, commences, and extends as an almost continuous canyon to El Bado, a few miles be- Mainly from report by G. T. Quinby. 262 HYDROGRAPHY OF THE ARID REGIONS. low Tierra Amarilla. There are, as is usually the case along rivers of this type, some places, locally termed u rincons,” in which the valley becomes sufficiently broad for agricultural purposes. About Tierra Amarilla the third division of the river course is reached, having many of the characteristics of the lower part, the deposits in both of these divisions being probably of lacustrine origin. The perennial tributaries of the Chama, of which there are sixteen of notable importance, vary in size from mere rills in summer to creeks whose headwaters, lying well up in the mountains, have a strong per- sistent flow throughout the year. All of the tributaries entering the Chama below the Cebolla, with the exception of the Puerco or Salinas Creek, have broad sandy channels near their mouths, and thus in this portion of their course lose much water by seepage and evaporation. Their valleys are usually broad, and rise from the stream in gentle slopes on both sides, being bordered by irregular hills. In the case of the Puerco or Salinas Creek the canyons near its mouth keep near the surface the water that would otherwise be disseminated through the sand, and on this account more water reaches the Chama. The loss of water in the Ojo Caliente, Oso, El Rito, Lower Canyones, and Cangilon is particularly large, and also, though to a somewhat less extent, in the Gallinas. There are two general topographic features of these streams, viz: the canyon portion, in which they descend rapidly from the mountains, and the valley portion of varying width, in which they flow gently to their outlets. On the Cebolla, Nutrias, and Nutritas the same characters exist, except that the valley portion consists of a mesa having a sheet of volcanic rock a short distance beneath the surface. The result is that a box canyon extends for a short distance from the mouth of the stream and checks in great measure the erosion above it, leaving a stream with a shallow bed flowing in a gentle depression. The Brazos, Canyones, Willow, and Little Chama belong rather to the first class of streams, those having broad valleys, but less water is lost, owing to the fact that for most of their length the sides and bot- toms are formed of compact clay and the bed is narrower. The Chama is essentially a muddy stream, and from its mouth as far up as the Gallinas Creek, not only is the Chama itself muddy, but every tributary is pouring into it a muddy torrent. Above the Gallinas the water is clearer, and its tributaries, especially the Brazos, less muddy. Taken as a whole, the Chama, however, is not so muddy as the Rio Grande south of Albuquerque, nor the Puerco below Nacimiento. The Chama and tributaries below the Cebolla carry also a considerable amount of soluble matter, and patches of alkali land are frequent. Above the Cebolla the larger streams carry but little alkali, but the smaller, particularly at low stages, apparently carry a large proportion. The alkali seems to be principally found in the lake deposits. NEWELL.] WATER-SUPPLY OF CHAMA DISTRICT. 263 The amount of water in any of the streams of the Cliama drainage system depends upon a wide range of modifying conditions. Most of the streams head in the mountains at an altitude of at least 8,000 feet, where the winter snowfall is usually very heavy. During the spring, while this snow is melting, the volume of the stream is swollen, and warm rains during this period are apt to produce sudden floods. After the snow has disappeared and throughout the summer occasional heavy rains cause a rapid increase in the volume of the discharge, followed by a decline almost as sudden. During the late summer and autumn the streams become low, receiving their water from the slow drainage of the grpund, and remain so until the snow again melts in the spring. The increase of volume over the outflow of ground water may therefore be divided into the regular yearly increase from melting, of which an approximate estimate may be made from the amount of snow at the headwaters of the streams and the spasmodic increase from torrential rains, an adequate measurement of which can be obtained only from systematic records. The volume of water at any point in the Chama or in any one of its tributaries depends upon two conditions : First, as has been noted, upon the weather, especially the precipitation during the season; and secondly, upon the portion of the stream at which the measurements are made — that is to say, upon the physical characteristics and struc- ture of the valley. A great loss of water in the lower portion is characteristic not only of the Chama, but also of all of its tributaries entering below the Cebolla. This loss is occasioned by the spreading of the stream into several shallow channels in a broad sandy bed of gentle slope. The streams entering the Chama are briefly described in order upstream, the discharge of each being given as ascertained by measurements made in March and April, 1889. Oso Creek is a small stream entering the Chama from the south about 8 or 10 miles above Chamita. Its flood bed is broad and sandy, but in ordi- nary stages a mere thread of water flows in it. There is a brush darn near the mouth, the water being taken into the Chama Valley, as that of the Oso is very small and irregular and bordered by broken and greatly eroded hills. The discharge of the Oso March 26, 1889, was 5 second-feet. Ojo Caliente Creek, which flows into the Chama nearly opposite Oso Creek, was measured several times and found to carry during the win- ter of 1888-’89 from 33 to 50 feet. The creek was higher on March 26, 1889, and was discharging about 75 second-feet. El Eito Creek enters the Chama Valley from the north, as a small stream flowing in a flood channel nearly 200 yards in width, with banks about 8 feet in height. The valley near the mouth is narrow and the stream bed broad, but 10 or 12 miles above this poiut the valley widens, considerably. Some 3 miles above the town of El Eito the river leaves a canyon, within which the measured discharge was found to be 33 2G4 HYDROGRAPHY OF THE ARID REGIONS. second-feet in March, 1889. The stream at that time had evidently not acquired the full volume from the melting’ snow. At the same time the El Rito was flowing 9 second-feet at the point above where it empties into the drama, the loss being probably due to evaporation and seepage. The Frijoles is a small stream joining the Chama from the south, above Abiquiu. The bed is probably dry in summer ; on March 28, 1889, however, the discharge was about 5 second-feet. The valley along this stream is of inconsiderable size. The Canyoues also enters the Chama from the south, at the lower end of a large rincon called the Vega del Riego, from a Mexican ranch in it, this point being at the upper end of the sandstone canyon above Abi- quiu. The valley is sandy at its mouth, and is narrow and bordered by sandstone mesas. On March 28, 1889, the discharge was 14 secoiql- feet, but the water was muddy, showing that the stream was somewhat swollen. In summer the bed must be dry for some distance above the outlet. Cangilon Creek flows into the Chama from the north through a great arroyo called the Rio Seco, in passing through which a large amount of water is lost. There are openings along the course of the Cangilon containing in all several hundred acres of good bottom land. The dis- charge of the stream after it had emerged from Navajo canyon was found to be 28 second-feet on March 30 and 45 second-feet on April 5, 1889. The water was muddy, due to rapid melting of the snow. It is reported that the Cangilon at this point flows throughout the summer. Gallinas Creek is a muddy stream entering the Chama from the south in a comparatively narrow, sandy valley, bordered on both sides by high sandstone mesas. The bed is sandy, and the water is spread over it in a thin sheet. Irrigation in the valley is confined to the vicinity of the town of Gallinas, some 15 or 20 miles above the mouth of the creek. The Gallinas was flowing 12 second-feet at its mouth March 29, 1889, and April 7, at Gallinas, about 20 second-feet. Cebolla Creek enters the Chama from the east bank through a lava canyon. Above the canyon it flows through a. valley, broad in compar- ison to the size of the stream, and with a gradual rise on each side. There is little sandy soil in the valley, but the water supply is too small to irrigate even the bottom land of the stream. With more water an enormous tract could be brought under ditch. The stream is of the type of those having clay banks, soft shale outcropping at various points in the valley, and it reaches hard rock only when it cuts through the lava sheet at its mouth. It was very muddy, flowing 12 second-feet when gauged on March 31, 1889. The discharge during summer must be very small, but it is reported that there is always some water in the channel. Nutrias Creek also empties into the Chama from the eastern side, a few miles above the Cebolla. This valley is topographically almost identical with that of the Cebolla, and is characterized also by the great disparity between the amount of land in the valley suited for irrigation and the NEWELL. J TRIBUTARIES OF THE CHAMA. 265 small amount of water in the stream. The water of this stream was less muddy than that of the other streams above mentioned. The discharge was 10 second-feet on April 1, 18S9, at the Lopez ranch, at the entrance to the canyon, below all irrigation. The Nutritas also flows into the Chama from the east bank, a short distance above the mouth of the Nutrias and is similar to the Cebolla and Nutrias, except that this valley is somewhat narrower. Water from the Nutritas is taken out a short distance above Tierra Amarilla, and brought upon a mesa extending from that place to Park View on the Chama. There is only enough water, however, to show what might be done were it practicable in any way to increase the supply. Above Tierra Amarilla the valley rises very gradually on each side of the stream in great undulations covered by forests of long-leaf pine, none of this land being cultivated. There seems to be no surplus water in the Cebolla, Nutrias or Nutritas. The Nutritas was flowing April 1, at a point about 5 miles below Tierra Amarilla, 20 second-feet. The Brazos is the most important tributary to the Chama, flowing into it from the east about 2 miles above Tierra Amarilla. It is formed from two streams heading high in the Tierra Amarilla Mountains, near Brazos Peak. The lower valley is broad and cultivated, but the stream flows through this in a wide, pebbly bed. From about 2 miles above its mouth to the point where it leaves the canyon it is bordered on both sides by gently rolling land covered by pine forests, which when cleared will yield valuable timber and leave several thousand acres of irrigable land. None of this pine land above Ensenada is cleared, although a couple of irrigating ditches are brought through it. The bed of the Brazos has the bowlder-strewn character of a moun- tain brook, and its fall is rapid ; even in stages of high water the stream is clear. On April 2, 1889, the discharge was 150 second-feet, and much of the snow in the mountains had not then melted. It is stated that the Brazos continues to discharge all summer an amount of water nearly as great as this. The Canyones and Willow Creeks are two small streams entering the Chama from the east bank. They have very small catchment areas, and were flowing on April 4, 1889, 8 and 12 second-feet respectively. It is probable that in summer they are nearly if not quite dry. There is no cultivation in these valleys, but iu places some hay is cut. The Little Chama is the name given to the western fork of the Chama, which joins the main stream about 2.j miles below the town of Chama, flowing in a broad valley, and having steep clay banks. At, the time when measured the snow was melting rapidly, and the stream was flow- ing bank full, and besides this, every wash and arroyo was pouring a flood of muddy water into it. It is evident, therefore, that its volume of 95 second-feet is much above the average. 266 HYDROGRAPHY OF THE ARID REGIONS. Summary of water flowing in the tributaries of the Chama, as measured March 26 to April 4, 1S89. Second-feet. 1. Oso 5 2. Ojo Cali elite 75 3. El Rito 33 4. Frijoles 5 5. Canyones (Lower) 14 6. Cangilon 28 7. Puerco or Saliua , 40 8. Galliuas 12 9. Cebolla 12 10. Nutrias 10 11. Nutritas 26 12. Brazos 150 13. Canyones (Upper) 8 14. Willow 12 15. Little Chama 95 Total 525 This estimate does not include the water in the main branch of the Chama above the town of Chama, which must have been flowing at the rate of at least 300 second-feet. The total discharge of the Chama at Abiquiu at this time was estimated to be 750 second-feet. Beginning at Chamita, a small Mexican town at the mouth of the river, having an altitude of 5,G19 feet, the Chama Valley rises to the northward, the increase in elevation being accompanied by colder cli- mate. At Abiquiu the altitude is 5,930 feet, but the climate is re- ported to be similar to that at Espanola, the Jemez Mountains to the south and rising land to the west and north affording ample shelter. From Abiquiu the land rises steadily to the west and north, and at Tierra Amarilla an altitude of 7,4G6 feet is reached. Here frosts occur in May, and are not uncommon even as late as the latter part of June. Much snow falls during the winter, and remains upon the ground until late in the spring. At Chama the elevation is 7,840, feet and snow usually remains upon the ground until about the first of May or eveu later. Although the summer season throughout this country is short, it does not appear to have a deterrent effect upon agriculture in general, except that some of the more sensitive fruits and crops are not raised, and although the winters are colder than those of the Bio Grande Valley and the snowfall heavier, still winters as cold and snows as deep are successfully encountered by farmers in other sections of the country. There is a great compensation, however, in the increased and prolonged si>ring water supply. As much as 40 per cent of the irrigable land may be considered as under ditch in the Chama Valley, not including the great area of lava mesa or the upper portion of the valley. In proportion to the amount of land in the valley suitable for irrigation the El Bito appears to have NEWELL.] IRRIGATION IN CHAMA VALLEY. 267 most land under ditch, and the Vega del Riego and upper Chama, above Los Brazos, the least. In at least two cases, one above Ensenada on the Brazos, and one above Los Brazos on the Chama, a ditch ran for several miles through timbered land from which the trees had not been cleared, nor the water used on the route. Much land is also under ditch and not used on account of the peculiar location of the little isolated ranches, to water which the owner has been compelled to take water from the stream some distance above the place on which it is to be used, tbe in- tervening land thus being brought under ditch, although not owned by the irrigator. The amount of land under crop is small, and in no instance has any- thing like farming on a large scale been adopted. For a large portion of the country the railways are so distant that it would appear imprac- ticable for a farmer to attempt to raise crops larger than required for his own use, or for the limited demand of some merchant. Only in three localities is there anything approaching a general cultivation of the land. These are at Tierra Amarilla and surrounding towns, at that part of the valley between Chamita and Abiquiu, and also about the town of El Rito. In all the rest of the valley, not taking into account scattered ranches along the tributaries, the amount of irrigated land would not exceed 1,000 acres. Summary of the estimates of irrigation. Localities. Irrigable. Under ditch. Actually under crop. Acres. 20, 000 6, 000 20, 000 10, 000 9,000 35, 000 Acres. 10, 000 3, 000 Acres. 2,100 400 4, 000 5, 000 8, 000 600 1,300 1, 100 100, 000 30, 000 5,500 These estimates are probably too small as regards the amount of irri- gable land, which may prove to be uearly 50 per cent greater than is given. In the Chama Valley as at Taos, with but few exceptions, the water is applied to the soil by flooding “squares” or small rectangles sur- rounded by ridges of earth, this system of taking the water directly from the main ditch and allowing it to flow from square to square being general throughout New Mexico. Apparently when the water is al- lowed to flow unchecked over the land, the finer sediment can be de- posited only in the most favorable places, and thus quite as much soil is washed from the land as is deposited upon it. In the case of grass, however, after the squares are full the flow is checked, and the water kept upon the ground for some time. Thus not only does the finer material have time to settle, but the soil itself 2G8 HYDROGRAPHY OF THE ARID REGIONS. is more thoroughly soaked with water. The general opinion of the irri- gators is that as now cultivated land decreases in productiveness with constant cropping. At those localities however, where this holding the water between ridges or “checks” is practiced, the decrease in produc- tiveness is said to be less. Wheat, oats, peas, beans, barley, corn, and potatoes are the principal crops raised in the Chama Valley. “ Rust” or “smut,” a parasitic growth, is oue of the plagues of the wheat growers, particularly in the neighborhood of Tierra Amarilla. The “lady bug” is a source of con- siderable damage to the bean crop, often resulting in its partial destruc- tion. The yield per acre of wheat is variously estimated throughout the valley, but on successful farms a little over 20 bushels per acre is probably a fair average. Potatoes are little grown by the Mexicans, but other inhabitants find no difficulty in raising good crops. At higher altitudes, particularly near the mountains, potatoes could, without doubt, be raised without irrigation. Corn is grown only to a small extent in the upper Chama Valley, principally from the fact that it matures somewhat later in the summer than the other crops, and when water is too scanty for the tinal irrigation. Alfalfa is not a common crop, but more is being sown each year, and it is reported that three good crops can be cut. Fruit and grapes are grown in the lower part of the valley and about El Rito. Some fruit is also raised about Tierra Amarilla, and there can be but little doubt that suitable varieties of apples, pears, and the more hardy fruits can be raised all through the valley. The soil throughout the Chama Valley is in general composed of a mixture of sand and clay, the clay usually in excess. An exception may be made to this statement in the case of the lower portion of the Chama Valley, which is very sandy. The valleys of the upper tribu- taries, and indeed of the upper Chama itself, have a decidedly clay character, while the ridges and higher ground are usually more sandy. The testimony appears almost entirely on the side of the opinion that when properly irrigated the land suffers no decrease in productiveness from continuous cropping. Instances are cited in which land cropped continuously for 10 or 12 years was supposed actually to have gained in productiveness. In the lower Chama Valley there is probably a large amount of silt deposited upon the land, but in the vicinity of Tierra Amarilla the streams are clearer, and a smaller amount is deposited. So far as ascertained there is no canal company in the Chama Valley selling water. All the ditches are owned either by communities or by individuals, and no record is kept of the cost of putting water upon land. The realization that time has a money value is almost unknown among Mexicans. When they can do anything themselves, they take no ac- count either of their time or labor. This is shown in many localities in New Mexico where brush dams, requiring yearly a great amount of labor, are common. The farming in the Chama Valley is done almost NEWELL.] WATER SUPPLY OF SANTA FE VALLEY. 261 ) entirely by Mexicans, the few inhabitants of other nationality being- cattle men, miners and storekeepers, and on this account it has been found a matter of great difficulty to obtain reliable estimates. Local regulations regarding the distribution of water differ in almost every town, apparently having grown up from a mixture of Spanish and Indian customs. The customs of the Pueblo Indians are essentially communal, and have left a strong impression upon the local rules now enforced, as embodied in the major-domo system, whose code is largely unwritten, but is enforced at least among the Mexicans. In some portions of the territory water is given to the user strictly by time; in others, by the actual need of his crop for it; in others, according to the amount of land that he has under crop ; and yet again, according to the amount of work he has done in repairing and clearing- out the ditch. The ditch itself is built and maintained by the joint labor of the community, and is common property in the strict sense. No one is allowed to take water from the ditch unless he has either personally or by proxy done the task assigned him by the major-domo, either in the construction or in the maintenance of the ditch. As in the case of the Taos Valley, the major-domo is elected every spring, and has charge of everything connected with irrigation. In some places he is paid a small salary during the spring months; in others his services are voluntary, except that he is exempt from work on the ditch. SANTA FE DISTRICT. The streams of which Santa Fe Creek is the chief and which enter the Rio Grande south of the Espanola Valley can be considered as forming a division by themselves. These rise in the range east of Santa Fe and flow westerly over high plains to join the river. In the mountains at the head of Santa Fe Creek are two small lakes, which may be considered as typical of those at the head waters of other streams flowing- towards the Rio Grande. Many of these can be utilized as small storage reservoirs by constructing dams at the outlets. A de- scription of one will serve to show the conditions surrounding them. At the head of Santa Fe Canyon is a lake about 4 acres in area, with a depth of 20 feet. Formerly this lake was larger, but some years ago an outlet was cut reducing the level by about 0 feet. This outlet can be closed by a dam and suitable gates, so that the level of the water can be raised at least 15 feet, forming a reservoir of small size, the sur- face area being between 5 and 0 acres in extent. In September, 1889, at the driest time of the year, a stream of about 2 second-feet was flow- ing from the lake. By the utilization of this and other small reservoirs the summer flow of Santa Fe Creek can be increased, sufficiently at least to be of great benefit to the agricultural land at the time when, by reason of low water, many of the crops, and even fruit trees, are injured by drought. The elevation of these ponds is about 11,000 feet, and the evaporation is very small, since they are surrounded and protected by the mountain peaks. 270 HYDROGRAPHY OF THE ARID REGIONS. Along the valley of the Santa Fe Creek, below Santa Fe, but a small amount of land is cultivated. Agriculture is limited by the small amount of water that can be depended upon during the growing season. The stream runs through a valley with gradually sloping sides as far as Ciene- guilla, a Mexican town about 12 miles from Santa Fe. At Cieneguilla the stream enters the La Bajada Canyon, which is deep and narrow as far as the town of La Bajada, below which is a broader valley with a gentle slope to the left and the edge of the mesa to the right. This valley con- tinues almost to the mouth of the creek, a distance of some 6 or 7 miles. The mesa between La Bajada and Pena Blanca, on the Rio Grande, has a smooth surface and gentle slope, so that water could be brought from La Bajada Canyon and many thousand acres be put under ditch, if sufficient water could be obtained by storage or other means. Dur- ing the spring months a large amount of water passes through the canyon, and it is probable that much water might be saved in the canyon even by dams of a temporary character, such, for example, as are used on the Puerco. In the neighborhood of Pena Blanca the laud is as thoroughly culti- vated as in any part of the Rio Grande Valley. Grain fields, orchards and vineyards abound, and the ditches are carried back close around the base of conglomerate-capped sand hills that mark the edge of the valley, so that there is but little land not under ditch. Four miles down the Rio Grande, near the mouth of the Gallisteo, the first creek south of the Santa Fe, is the pueblo of Santo Domingo, and several miles up the creek above this is the town of Wallace. A very deep ditch runs across the little divide between the Rio Grande and Gallisteo Creek, and, although the land is well adapted for irriga- tion, the water is not used along the ditch, but only at distant points. The Gallisteo Creek was dry when examined in January, 1889, but showed signs of frequently carrying large amounts of water, and the railway company has done considerable work to prevent it from en- croaching upon their track. It drains a large watershed, and toward the headwaters a constant stream flows in the channel. ALBUQUERQUE DISTRICT. Under this name can be included all the Rio Grande Valley from Pena Blanca to San Marcial. The valley is narrow, being at no place over 3 miles wide, and at many points the bounding hills or mesas approach each other so closely that no room is left for bottom lands. Around Bernalillo, Albuquerque, and Belen are areas of cultivated land of excellent quality and some large vineyards; the extent, however, is not as great as in the Mesilla Valley further down the river. Below Bernalillo and also below Belen on the east side of the river are large alkali flats, once productive fields, but now worthless from lack of drainage. The river from Pena Blanca to San Marcial occupies a broad sandy NEWELL,] THE RIO GRANDE VALLEY. 271 bed, dividing in low stages into a number of narrow and crooked channels, but in flood covering in many places nearly half of the valley. Above the pueblo of San Felipe, for a distance of from 6 to S miles, a large percentage of the valley is under ditch. At San Felipe the valley narrows, and between the San Felipe and Algodones Creeks a large part of the agricultural land seems to have been deserted, and several of the higher ditches have been abandoned. This is possibly the effect of the Santo Domingo and San Felipe grants, which cover nine-tenths of the valley between Santo Domingo and Algodones, and are much larger than the Indians can cultivate under present conditions. NT ear Bernalillo the many vineyards and orchards give to the country an appearance of prosperity. The same may be said of the valley between Bernalillo and Alameda, about half way to Albuquerque, although a large portion of the area is occupied by the broad river bed. The country about Bernalillo is one ot the wine-producing centers of the valley, and is reputed to have the largest distillery in the territory. Near Albuquerque is more waste land, and the valley is bordered by barren hills of blown sand. This sand settles in and around the low bushes of the valley, forming hillocks, which give this portion of the valley a curious appearance. Much of the land is fenced and is devoted to raising a scanty supply of a coarse grass for grazing purposes. The vineyards and orchards are smaller, and there does not seem to be the same thrift and prosperity as about Bernalillo. From Albuquerque to Los Lunas, a distance of some 25 miles, the the western side of the valley is broader, and has great hills of wind- blown sand for its border. Only the lower and more accessible parts of the valley are irrigated, although there is a large amount of rather sandy land which is still capable of cultivation, and which could easily be brought under ditch. The valley as far below Albuquerque as Pajarito, about 8 miles, is thickly inhabited, but the average amount of land per family cultivated among the Mexicans is very small, not exceeding a couple of acres. The number of English-speaking agri- culturists in the valley is insignificant. From Albuquerque to San Marcial the drainage of the lower lands of the Rio Grande Yalley is exceedingly poor. Many ponds, some of them 8 or 10 acres in extent, are full of water during the early part of the year, and others show by the alkali coating on their sides and bottoms that the water has but recently left them. This alkali coating is so universal between Los Lunas and Belen as to give to the casual observer the impression of a light snow. Apparently the Mexicans have no system either of surface or under drainage, without which it is doubtful if much further cultivation can be successfully accomplished. The ditches in this low land are liable to frequent overflow, and much damage is yearly done by their being washed out or being tilled with silt. HYDROGRAPHY OF THE ARID REGIONS. 272 Tlie pueblo of Isleta, 15 miles below Albuquerque, is said to be one of the richest in the Territory, and appears to be in a more prosperous condition than the neighboring Mexican towns. Between Isleta and Los Lunas is but little farming, but at Los Lunas the vineyards are im- portant and some wine is produced. Very little alfalfa is grown in this vicinity. From Los Lunas south the valley is thickly inhabited, and there is a succession of small clusters of Mexican houses. The same apparent lack of industry and thrift prevails as in many places along the river bottoms, and the disadvantages of living on the low tiats are shown in the number of houses which have fallen in by the sinking of the foun- dations. A large part of the valley south of Los Lunas is overgrown with cottonwood thickets or bosques, as they are called. Where these are cut away the land is found to be excellent. The vineyards seem to be thrifty and in good condition wherever care has been given, but the absence of orchards is notable. All along the sides of the valley, at elevations a little higher than the portions now cultivated, are lands which probably could be irrigated by higher and larger canals. The Rio Grande Valley below La Joya station, 53 miles south of Albuquerque, narrows again, and at San Acacia the river enters a canyon about 250 yards wide, the river occupying the greater part of this width, at ordinary stages running through the sand in several channels. Below San Acacia high bluffs on the west side of the river leave only a small strip of irrigable land some 0 or 8 miles to the south- ward. These bluffs are farther back from the river on the east side, so that more land can be utilized, and about 5 miles north of Socorro the valley becomes considerably broader. Throughout this section, and indeed all along the valley, farming is carried on upon a petty scale, and not more than one-third of the land is under ditch. From Socorro to San Marcial the character of the valley and its conditions are essen- tially the same as portions already described, there being perhaps more bosques and fewer settlements. Colonies have been started just above San Marcial, and also near Fort Craig. The methods of irrigation in this long valley are those of a past cen- tury; innumerable small ditches take water to the bottom lands only. Every town has its acequia, an unsurveyed, irregular ditch, built with- out method and controlled in a haphazard way. At the head .are brush dams, and along the course, whenever it crosses an arroyo, the ditch is liable at every rain to be washed out, and, at nearly every road cross- ing, its banks are worn down by animals and wagons. The acequias are the common property of the people using them, the water tax con- sisting in a share of work in the ditch repairs, an amount depending upon the quantity of land irrigated. The water is supplied by the hour, a man being allowed certain days and nights in his turn, during which time he may fill his “ contra acequia.” The major-domo who distri- butes the water is supposed to see that each man gets his proper share, reckoned in hours, and that his head gate is closed at the proper time. NEWELL.] CONDITION OF IRRIGATION IN SANTA FE VALLEY. 273 The results of this rather loose system are both beneficial and inju- rious ; beneficial in that any man, even the poorest, can pay his water tax; injurious in that no one is responsible for a continuous supply of water, and because the system, once started, is seldom or never im- proved, and such systems are almost always begun on a very small scale. Irrigation along the Rio Grande is in practically the same condition as when the Spaniards first passed up the valley. Some few new cus- toms have been introduced, but the system is essentially the old Pueblo Indian system. If anything, the Indians are now in advance of the native Mexicans. Their farms are better kept, their ditches are more regular and cleaner, and their harvests are apparently more bountiful. They are more thrifty, and having a common interest they work together with less conflict than their neighbors. There are comparatively few fruit trees or vines in this part of the ' valley. Occasionally an “American” ranch is passed or the farm of a wealthy Mexican, and here are almost always trees and vines in small patches. The general appearance of lack of industry in attempting permanent improvements is due, in part, to that inherent peculiarity of the natives, freedom from all thought of the future, and in part to the uncertain state of the water supply. A few acres of corn, a small patch of wheat, and a garden of chile and onions usually suffice. It would be difficult to find another valley, settled for hundreds of years, as favora- ble to agriculture as this, which shows so few signs of activity. The soil is capable of producing anything that will grow in a warm, temper- ate climate; yet in most places corn, wheat, and oats remain the staple crops. The land in the Albuquerque Valley is for the most part excellent, portions of it, however, being subject to overflow, and other portions, as before mentioned, containing quantities of alkali. In general, it is a rich deposit of silt on the old river flood plain. Near the mesa the plain gradually passes into hummocks, layers of sand and gravel, the height of the mesa above the river varying from 15 to 50 feet, or even more. There is no doubt that the water of the Rio Grande can be led upon a part of this mesa, the soil of which is often very fertile, in places consisting of weathered basalt, although in general it is made up of water- washed gravels. TRIBUTARIES BELOW THE CHAMA. SANTA FK ANI) ADJACENT STREAMS. In the following paragraphs a brief summary is given of the principal streams entering the Albuquerque Valley. The first of these is Santa Fe Creek, which, as previously described, discharges a very small amount of water during the greater part of the year. Gallisteo Creek flows a large amount of flood water into the Rio Grande, but often is dry for miles above its mouth, as was the case in January and Febru- ary, 1889. For some 8 miles at least above its mouth it runs through 12 GEOL., PT. 2 18 274 HYDROGRAPHY OF THE ARID REGIONS. unconsolidated deposits, and in no place can anything approaching a fixed cross section be found. A small stream comes down through Bear Canyon, in the Sandias about east of Bernalillo, but the water all sinks within a mile or a mile and a half of the mouth of the canyon, except in times of flood. The same may be said of the stream in Tijeras Canyon, about 17 miles east of Albuquerque, except that there is an unusually good natural dam site at the mouth of this canyon. It has been proposed to make a dam at this spot, and conduct the waters held by it out upon the mesa on the east side, opposite Albuquerque. At the mouth of the canyon are excellent facilities for erecting the dam. The stream has cut through a mass of crystalline feldspathic rock, leaving an opening not more than 150 feet wide. The rock rises abruptly in a cliff on one side to a height of 80 or 90 feet above the level of the stream. As the valley opens out to a considerable width just above the point selected for a dam, ample room is given for a large volume of water. The stream in the latter part of January, 1889, was not flowing more than 2£ to 3 second-feet, but was reported to be larger in November, when the discharge was about second-feet, as shown by float gauging. This stream has cut back through the steep face of the Sandia Mountains, and drains a portion of the dip sur- face on the eastern side, thereby securing a larger drainage area than most of the small streams, and thus in flood a large amount of water is carried. The water can be brought to the surface of the mesa about 1 mile below the dam, and thence conducted over a practically indefinite amount of mesa land. Hell Canyon, some 20 miles southeast of Albuquerque, contains a small stream, but it too sinks within a short distance of the mouth of the canyon. At Abo Paso and several points to the south are streams of the same character, but it is doubtful if there is a single stream on the east side between Pena Blanca and San Marcial that flows at the rate of 5 second-feet, except in time of flood, and in many seasons not one of them delivers any water within 10 miles of the Rio Grande. West of the Albuquerque Valley are the large drainage areas of the Jemez and Puerco tributary to the Rio Grande. Little water flows from them during the summer. • In fact, it may be said that on the west bank not a single stream below Pena Blanca, with the possible excep- tion of the Jemez, reaches the Rio Grande, except during the annual freshets. The Salado comes in as an arroyo, about 8 miles north of Socorro. Water flows in it along the foot of Ladroues Peak, and some irrigation is done, but for the greater part of the distance it flows in a canyon. JEMEZ RIVER. The Jemez River enters the Rio Grande from the west at a point about 5 miles above the town of Bernalillo. It drains the country south of the Chama and west of the Santa Fe drainage. In the head- NEWELL.] TRIBUTARIES OF THE RIO GRANDE. 275 waters are many open valleys, at an elevation of 8,000 feet and upwards, in which are hay ranches and cultivated lands. There are several localities at which water can be held by the construction of suitable dams. Leaving the mountains the small tributaries enter narrow can- yons, finally uniting at the head of the Jemez Yalley, about 5 miles above Jemez Pueblo. This valley is from 1 to 3 miles in width. Its soil is in most places sandy, but with the application of water is very fertile. Agriculture is carried on to a small extent by the Jemez Indians and by the Mexi- cans at San Ysidro. Three miles below this latter town the Rio Salado comes in from the west through a broad, fertile valley. The valley continues to widen and contains large areas of excellent land. Small areas are cultivated by the Indians of Silla and Santa Ana, but the supply of water is deficient for their needs, or can not be diverted suc- cessfully from the river. The soil is very fertile and produces fine grapes, peaches, apples, corn, and vegetables. In this portion of its course the river occupies a wide, sandy channel, in which the greater part of the water disappears excepting in times of flood. Below the Santa Ana Pueblo the river enters a narrow canyon, through which it continues to its junction with the Rio Grande. Throughout the lower part of its course the river is bordered by mesas covered by arable lands, to a part of which at least water could be brought from points in or near the canyons of the various tributaries. The discharge of this river was measured at various times in 1889 and found to vary from 85 second-feet in the spring to 20 second-feet in October. This was a year of unusual drought, and the floods were very low and of short duration. rUERCO RIVER. South and west of the Jemez is the Puerco, a river which though draining a large area is dry at its mouth during the winter and early spring. The valley is uninhabited from the mouth as far north as the point at which the Atlantic and Pacific Railroad crosses it. The water from its principal tributary, San Jose Creek, sinks within a few miles of its mouth, although it is the largest stream in that part of the Ter- ritory, and when others were dry was flowing from Cubero to its mouth. For 40 miles up the Puerco no water could be found in February, 1889. The divide between the Rio Grande and Puerco in its lower course, and in particular in the vicinity of Albuquerque, consists of a gently undulating mesa about 6 miles or less in width, bounded on both edges by sandy foothills. The valley at this point is about 2 miles wide, has a gentle slope, and the soil seems excellent, but very little attempt at farming has been made on account of the scarcity of water. On the west side of the valley are deserted ranches where some irri- gation has been done with the flood waters of small arroyos. It was evident from the wheat stubble and threshing floor that crops have 276 HYDROGRAPHY OF THE ARID REGIONS. been raised. Considerable quantities of native hay are usually cut by the Mexicans from a broad, gentle valley known as the Canyon del Ojo. At the junction of the Canyon del Ojo with the Puerco a Mexican farmer has put in a bank about 200 feet long by lit feet high behind which rain and Hood water is caught. This he lets to a cattle owner for $200 per year. The principal tributary of the Puerco is the San Jose, or, as known at the head waters, Bluewater Creek, which enters from the west. Be- low the Big Spring, near the town of San Jose, this creek was discharg- ing from 10 to 12 second-feet in February, 1889. West of San Jose, up the creek, is a broad valley expanding toward the south. The creek bed had water in it, but usually when not swelled by melting snows it is dry at this point. Some irrigation is done by the Mexicans at the town of El Rito, about 15 miles below San Jose, but it is insignificant in amount. About 12 miles below San Jose and between it and El Rito is the pueblo of Laguna, whose name, Lake Pueblo, is said to be derived from a former sheet of water made by an artificial dam erected by the Indians a few miles above the pueblo. This lake was probably from 130 to 160 acres in extent, and must have been from 10 to 12 feet deep in places. Nearly a quarter of the land formerly covered by the water from this lake is now occupied by crescent- shaped hills of blown sand. The dam was washed away in 1859 or 1860, and has not been rebuilt. Crops are grown in its basin, however, and a small carp pond is still preserved. From the upper end of the San Jose Canyon clear to the head of the principal tributary, the Bluewater, along the line of the Atlantic and Pacific Railroad, is a valley at an altitude of 6,500 feet and of varying width, but of great fertility. A small portion is covered by a lava flow reaching from McCarty’s west and north to Bluewater. Water for this extensive region can be had only by storage, but with this the region will become wonderfully productive. At present there are few inhab- itants besides the Laguna and Acoma Indians and a settlement of Mex- icans around Cubero. The San Jose, although in ordinary seasons small, must discharge an enormous quantity of flood water, for its drain- age area is very great. The stream flows constantly at all seasons for some 3 miles below Laguna, where it evaporates in summer. On the head of the Puerco, in the San Joaquin del Nacimiento grant, northwest of Jemez, is a beautiful valley covering an area some 15 miles long by 6 wide. It is so high that nothing but small grain can be raised, but the soil is extremely rich, and could a water supply be obtained, it would become a valuable tract of land. There is, however, no adequate water supply visible, and apparently this valley Avill long remain among the undeveloped resources of New Mexico. Farther south also are other valleys and bottom lands with little or no water for irrigation. The Puerco holds a constant stream as far south as Casa Salazar, a point almost west of Jemez, and from there on the water is caught by NEWELL.] WATER SUPPLY OF RIO GRANDE VALLEY. 277 the Mexicans during the floods in brush dams. Each year brush and rocks are put in the bed of the stream and are filled with silt, forming a rough dam. The water detained, in this manner is used for irrigating, but the whole arrangement is washed away in the winter and the process is repeated the next spring. This system is also used at points along the San Jose Creek. It is found to be the only one practicable, as it would be very difficult to put in a permanent dam on the day founda- tions, which are over 100 feet deep, and rock does not appear anywhere near the river. As a whole, the land in the Puerco Valley seems of excellent quality, and less alkaline than the land in the Rio Grande V alley. There is a large amount of land farther down in the Puerco Valley with a gradual slope toward the river, in all, perhaps, upward of 100 square miles. The strip is probably 70 miles long, and averages about a mile and a half in width. Little or nothing can be done with tins un- less a large amount of water can be stored, and in many parts of the valley there are few places favorable for the erection of dams. Even if a sufficient surplus of water could be stored near the headwaters to bring this land under ditch, still the water would have to be conveyed some SO or 90 miles to reach the lower part of the valley, and it could be more easily brought upon one of the mesas above, where it could command a greater amount of land in a more compact form. The land throughout the Puerco Valley is of excellent quality, but the irrigation in the lower part of the valley seems to be confined to the small patches to which water held by the brush dams can be conducted. RfSSUMfi OP WATER SUPPLY. To recapitulate, the principal sources of water supply above and ad- joining the Albuquerque Valley are as follows: The Chama and Jemez are the only tributaries coming into the Rio Grande between Embudo and San Marcial that flow any considerable amount of water except in times of flood; the Santa Cruz, San Ildefonso, and Santa Clara, enter the Rio Grande in the Espanola Valley, but are insignificant in size; the Gallisteo and Salado discharge a considerable quantity of water in flood, but ordinarily are mere arroyos for miles from their mouth. Between Embudo and San Marcial it has been estimated that there are about 400 square miles of irrigable land in the Rio Grande Valley. This land extends in a strip of over 200 miles in length, and will average about 2 miles in width. The White Rock Canyon, extending from San Ildefonso to Pena Blanca, and separating the Espanola and Albuquer- que Valleys, is the only considerable canyon. The methods of irrigation throughout tin 1 whole valley are very similar in character; the ditches are short, and the water is used first on the lowest levels, and gradually as more land is needed the higher levels are reached. The water is taken from the main ditch and applied di- rectly to the highest of the small squares into which the tilled land is 278 HYDROGRAPHY OF THE ARID REGIONS. divided, lateral ditches being uncommon. When this one is full, the surplus water is allowed to run into the next square below it, and so on until the lowest square is reached. Much damage is done annually to the lower ditches by the overflowing of the river and the consequent filling up or washing out of the ditches. In short, irrigation along the Rio Grande is limited to narrow strips on either side of the stream. The valleys are narrow, and the amount of land with gentle slope suited to irrigation is comparatively small. The amount of surface water that stands in ponds through the lower part of the valley shows that in places, at least, considerable drainage is necessary, but it is doubtful if many of the native cultivators are able to make any outlay in draining aud improving their land, in addition to the yearly expense for repairs to the acequias. MESAS ALONG THE RIO GRANDE. East of the Albuquerque Valley is a long mesa running from the San- dia Mountains on the north to Socorro on the south, and lying at an ele- vation of from 300 to 600 feet or more above the river. There is much fertile land on this mesa, but it lies so high that water can not be brought upon it except at enormous expense. South of this is the Jornada del Muerto, the largest unbroken mesa in New Mexico, extending from Carthage on the north to the vicinity of Fort Selden on the south, a distance of about 100 miles. It is in places 35 miles in width, and is bounded on the east by the Sierra Oscura, San Andres, and Organ Mountains, and on the west by the smaller range of mountains bordering the Rio Grande or by the river itself. The sur- face is to the eye apparently level, and is covered for the greater part of the year by a grass, furnishing feed for large herds of cattle. Wells have been drilled at various points, and water struck at a depth of about 300 feet, but this is often so impregnated with salts as to be worthless. The preliminary examinations made by this Survey show that in all probability it will be impracticable to bring water from the river upon this land, both on account of the expense and the deficiency of supply, and these level tracts with deep soil are apparently absolutely worth- less for agricultural purposes. The mountains bordering the plain are low and unfitted for storing water on account of the uncertain rainfall, and the snowfall does not accumulate. Many arroyos enter the plains but none cross them, and rarely the water from a “cloud burst” in these mountains reaches the Rio Grande. The Mesa Cuchillo Negro embraces a large extent of country west of the Rio Grande and opposite the Jornada del Muerto, lying along Rio Alamosa, Rio Cuchillo Negro, Rio Palomas, Arroyo Seco, Rio Animas, and Rio Perches. The valleys on these streams are all narrow and the bluffs high, above these being mesas containing much good laud. As the fall of these streams is rapid, it may be practicable to take water out of them on to the mesas, but before this can be done a patient study NEWELL.] RIO GRANDE IN SOUTHERN NEW MEXICO. 279 and examination of the ground must be made. The streams all head on the continental divide, and furnish a spring How which, if stored, could be used on these mesas. The valley bottoms lie from 300 to 500 feet below the mesas and have precipitous sides, thus making it difficult to take a ditch out of the river and carry it over the mesas. All mesa land must be irrigated, if at all, by waters stored in the upper valleys of the small streams. The development of irrigation work here, therefore, must consist in the de- signing of small systems of storage reservoirs and canals, work requir- ing much time in the examination of the country. MESILLA VALLEY. After leaving the Albuquerque Valley, for some miles below San Mar- cial, the river flows through a comparatively narrow bottom, which is not more than a quarter of a mile wide and is bordered in places by steep rocky bluffs, these disappearing farther down the river. Ten miles below San Marcial the bottom lands nearly or quite disappear, and on the left side the Fra Cristobal Mountains rise abruptly from the water’s edge; while on the right or west side the ground rises gradu- ally from the river’s bank to the foothills. The river channel continues of this character to a point below the little Mexican town of San Jose where, after contracting, the valley opens again to a width of about half a mile, and abruptly contracting again the river enters a canyon. This canyon extends for about 0 miles and varies in width from 500 to 1,500 feet at the high-water mark. The walls of the canyon are of gravel and conglomerate, overlaid by lava, which in some places, particularly on the left bank, reaches a thickness of 40 feet. The walls at the highest part are about 100 feet high, decreasing to 50 or 60 feet in places, and are cut by arroyos. Below this gorge the river again widens, and there are patches of irrigable land at the mouths of small creeks, but the river bottom itself is narrow, and the river bed, being nearly half a mile in width, occupies nearly all of the narrow valley. At Santa Barbara, about 10 or 12 miles above Rincon, there was formerly a large Mexican settlement in the valley, which here widens to a breadth of nearly 4 miles. The inhabitants are now gone and the village is in ruins. The probable reason is that their land became so water-soaked and saturated with alkali that they could raise nothing. By exercising a little care in drainage a few new settlers are now farm- ing just below. These alternations of narrow gorges and bottom lands continue nearly to Fort Selden. In this course are points at which the river bottom lands are between 5 and 6 miles in width. A very small part of this, however, is cultivated; probably there are not 100 acres of crops irri- gated. There are several points at which reservoirs could be made by placing dams across constrictions in the channel. Usually, however, 280 HYDROGRAPHY OF THE ARID REGIONS. the bed of the stream is deeply tilled with gravel, and it would be diffi- cult to obtain good foundations. These reservoir sites on the main river can be utilized for storing water for the Mesilla Valley, thus allowing the summer flow of the river to be freely used on lands farther north. Below Fort Selden the valley opens, and continues, in general, broad and fertile down to the constriction at El Paso. In this course is the Mesilla Valley, one of the best localities for fruit-growing along the Rio Grande. This valley, stretching from Fort Selden reservation on the north to the Texas line on the south, a distance of 35 miles, and with a width varying from 8 to 10 miles, includes land equal'to any in the United States for the cultivation of the vine and many varieties of fruit. Below the Texas line to El Paso, 15 miles farther down the river, the soil is nearly equally as fertile, but remains almost unculti- vated. The Mesilla Valley contains probably, all things considered, the most valuable land along the Rio Grande, and the necessity of providing an ample and permanent water supply is unquestioned. The soil is of wonderful fertility and great depth, but agriculture has made slow advances, on account of the uncertainty of the future supply of water. The continued diversions along the river for hundreds of miles above this valley render the inhabitants apprehensive as to their future. At the same time that water is supplied plans must be made for drainage, for the rich bottom lands tend to become water-logged, developing the alkaline crust, as is the case in valleys below Albuquerque. The amount of water flowing out from the Mesilla Valley for the last two years is shown graphically on PI. lxiii, the means and ex- tremes for each month being given in the tables appended. The gaug- ing station is located at Fort Bliss, a short distance above the town of El Paso, the measurements being made above the Mexican dam at that place and above the head works of all ditches or canals. This diagram should be compared with that showing the discharge at Embudo, and also that for Del Norte, the similarity of these being evident at a glance. The early spring floods at El Paso are especially notable, these evi- dently coming from tributaries below Embudo, since they do not appear on the sheet for that station. In briefly reviewing the use of water along the whole Rio Grande in Colorado and New Mexico, it is stated by Mr. W. W. Follettthat in the San Luis Valley, besides numerous ditches, there are five large canals with a combined carrying capacity of 8,000 second-feet, although few now carry over half their maximum flow. Even then 4,000 second-feet is being used in this valley, but of course much of this water finds its way back into the river at or above the canyon. Between Embudo and San Marcial about 1,000 second-feet are used, and in the Mesilla Valley, from Rincon to El Paso, 000 second-feet are needed. At El Paso the new ditch, which owns the water rights of the old ditches on the United States side, has a capacity of about 400 second-feet, and the Mexican ditches have a capacity of about 800 second-feet. DAILY DISCHARGE OF THE RIO GRANDE AT EL PASO, TEXAS. January. February. March. April. May. June. July. August. September. October. November. December. 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 UBfiAfiY Of THE UNIVERSITY of ILLINOIS NEWELL.] DISTRICT BETWEEN RIO GRANDE AND RECOS. 281 Thus there is needed to supply the demand below Embudo 3,100 second-feet, as roughly estimated. Seepage will cause some water to be used many times over, but even then, except in years of maximum flow, there will be a shortage of water. Then those valleys to suffer first will be the Mesilla and the Ysleta, in which the products are worth many times as much per acre as those of the land on which the water has been used. This shows the urgent need for reservoirs. With them the Territory of New Mexico can support a much larger population in the Rio Grande Valley, but without them her progress will be slow. GYPSUM PLAINS DISTRICT . 1 In southern New Mexico, between the Rio Grande and Pecos, are ex- tensive deserts, which for want of abetter name may be distinguished as the Gypsum Plains. These plains are the bottom lands of a vast basin completely surrounded by hills and mountains, and extending from about White Oaks nearly to El Paso, in Texas, a distance of more than 125 miles, with a width varying from 10 to 30 miles. On the north are the Oscuro and Jicarilla Mountains and foothills ; on the east the Sierra Blanca and Sacramento Mountains; on the south the Guadalupe and El Paso Mountains and foothills of the Hueco Mountains; and on the west the Organ, San Andres, and Oscuro Mountains. From each of these ranges numerous streams flow into the basin, but the water all disappears before reaching the center. Near the western margin of the plain, at the base of the San Andres range, is an extensive salt marsh, and to the south of this are the so-called White Sands, a gypsum for- mation. Portions of this plain can in time become agricultural land by stor- ing water among the higher mountains. The Sacramento, White, and Organ Mountains have a considerable depth of snow each winter and a heavy rainfall in the summer. These ranges are the only ones in this vicinity which otter opportunities for storing water. In the center of the Gypsum Plains near the northern end is a How of basalt, which, from all outward signs, appears to be recent, so modern in fact that there is a popular belief to the effect that it has been ejected since the Spanish invasion. At a point 15 or 20 miles north of the flow are the ruins of an ancient town ; and it is reported that traces of an extensive irrigating system may still be seen near the town. At present there is no water near the place, and the canals are said to be tilted at different angles. The basalt stream is fully 30 or 35 miles in length, and has a width varying from one-quarter of a mile to 4 miles. On the northeast of the plains is the Sierra Blanca Peak, the highest in the White Mountains, having an elevation of 11,892 feet, and wear- ing a cap of snow during the greater part of the year. There are nu- merous peaks over 8,000 feet high upon which the snowfall is very deep. 'From report l>y It. S. Tarr, 1889. 282 HYDROGRAPHY OF THE ARID REGIONS. The streams flowing from these mountains towards the west sink shortly after leaving the foothills. Among these the most important are Tularosa, Bonito, and Ties Rios. On each of these along the lower valleys farming is done by irrigation, and higher up in the mountain valleys good crops of oats, corn, and potatoes are raised without irriga- tion. Among the lofty peaks, deeply cut by erosion, covered with snow and drained by numerous constantly flowing streams, are probably a number of valuable reservoir sites. These will be of great utility, for to the south and southwest are the plains of almost unlimited extent at present, on account of the scarcity of water, not even grazed by cattle. PECOS RIVER. GENERAL TOPOGRAPHY. The Pecos , 1 rising on the eastern side of the Santa Fe Range, flows for a while as a typical mountain stream through narrow valleys and deeply cut gorges, then leaving the tilted rocks, cuts the horizontal strata of the mesa country, this horizontal character of the rocks pre- vailing throughout the Pecos Valley. Among the sandstones the coun- try is eroded and broken by arroyos, and the amount of agricultural land is necessarily small. Below Fort Sumner, however, the topography of the valley changes. The canyon-like walls disappear, and are replaced by low rolling hills. The ascent from the river on each side becomes more and more gentle toward the south, until near Roswell there is an imperceptible gradation from the flood plain to the prairie, this change in the topog- raphy being due to change in the character of the rocks, limestone and gypsum prevailing throughout this flue agricultural land. Arroyos and gulches become rare and canyons are practically unknown, the passage from canyons to prairie land being very gradual. The drainage of the lower Pecos in New Mexico is very imperfect, and there are broad tracts of country having no surface drainage what- soever. The water sinks into limestone rocks, and establishes an underground drainage. The consequence of this is the formation of numerous shallow “dry lakes,” which are in reality sink holes, many of these draining large areas. These contain water each year, and it is a constant surprise to the people of the country that they do not leave an alkaline crust upon disappearing, as would result if the water escaped by evaporation. East of the Pecos is the rolling prairie country of the Staked Plain, and to the west the White and other mountain chains rise out of the broken plain. The Pecos Valley is without doubt one of the finest in New Mexico, yet it has been unknown and little developed. The reason for this is that it has been for years, and indeed until very recently, the border land of civilization. Apaches, Comanches, and Navajos had their battle 1 From report by R. S. Tarr, 1889. NEWELL.] CHARACTERISTICS OF PECOS VALLEY. 283 grounds hero and made war upon their common enemy, the white man. Life and property were not safe, and none but the boldest of frontiers- men had the hardihood to brave the danger, the peaceful agriculturist finding no secure place. The fine grazing land, the abundance of water, and the wildness of the life attracted only the adventurous cattlemen, who came in from Texas, Arkansas, and the surrounding territories, and developed an extensive cattle industry. Farming being considered as an interference with cattle raising, farmers were prevented even by violence from settling, and the country was held for cattle only; but by the overstocking of the ranges and the low price of cattle the owners have become so impover- ished that they are in many cases forced to look to other means of self- support, and efforts are now being made to develop agricultural re- sources. On the middle Pecos near the river are two classes of land — bottom land and mesa. On the lower Pecos the bottom land is also present, but the mesa is replaced by prairie. In both divisions on approaching the mountains the country becomes broken into foothills. The bottom land is irrigable, yet not one acre in a hundred has been reclaimed. It has a rich deposit of silt, uniformly level, and capable of a high state of cultivation. It is estimated that there are between 250,000 and 300,000 acres of this land lying in a narrow strip on the middle Pecos, but broad- ening out southward to an average width of probably 2 miles or more. A portion of it is subject to overflow, especially along the lower Pecos. In such places there is considerable alkali, though by no means as much as in similar portions on the Kio Grande. The mesa land has a fairly good soil, in general rather thin, and com- posed entirely of weathered sandstone. Being high above the river and deeply cut by arroyos, it is not well placed nor suited for irrigation, and it is doubtful if any considerable portion of this upland country will be tilled. The prairie country, on account of its excellent soil, level char- acter, and slight elevation above the river, is well suited for irrigation and offers excellent opportunities for reclamation. CLIMATE AND WATER SUPPLY. The climate of the Pecos Valley is typical of the arid country in which the rainfall is from 12 to 15 inches per year. In descending the valley both the elevation and the latitude become less, and there is a gradual change toward a warmer climate. The entire valley is well suited to grape culture, and at Boswell the climate is similar to that of Las Cruces on the Kio Grande. Some snow falls every winter, but in the southern portion of the valley it rapidly disappears. The rainfall comes mainly in June, July, and August, in the form of showers, and is therefore extremely variable and uncertain. The main Pecos is formed by the confluence of the Gallinas with the Pecos at La Junta. Water flows perennially in these streams, at least 284 HYDROGRAPHY OF THE ARID REGIONS. as far down as the Atchison, Topeka and Santa Fe Railroad, but be- tween this line and La Junta the water entirely disappears by evapora- tion and seepage during many months of the year. On January 30, 1889, the bed of the Pecos at Las Colonias was so dry that a well 15 feet deep barely furnished a water supply for the stock and citizens of that town. A mile or two above Eden some small springs flow into the Pecos, and from this point the river channel constantly contains water. The river valley shows signs of powerful erosion, due to the floods of the spring and summer months. North of Puerto de Luna the river has a rapid slope, and is kept within its banks in time of flood, but below this point the water becomes more and more sluggish and muddy. In time of flood it overflows the flood plains extensively, but in low water meanders about among sand bars in the river bed. Above the Agua Negra Chi- quita, near Santa Rosa, the water is practically free from alkali, but this stream and every one south of it add to its alkaline character. UPPER fRIISUTARIES. The most important tributaries of the middle Pecos, because of the constant source of supply, are the Agua Negra and Agua Negra Chiquita, entering just above Puerto de Luna. The latter on the east side of the river receives an unfailing supply of water from two large alkaline springs. The smaller rises out of the ground in a canyon about three miles from the Pecos, and carries, it is estimated, C second-feet. The larger spring has its source about a mile and a half from the Pecos, at the base of a low sandstone cliff on the edge of an alkaline marsh. It is remarkable for its size and depth, the basin of the spring having a diameter of about 70 feet, and a stream of water flows from it carrying about 15 second-feet, receiving additions from numerous small springs on the way through the marsh to the Pecos. The Agua Negra flows from the Canyon Pintado, a very long arroyo on the west side of the Pecos, draining a large area of mesa country on the east side of the Manzano Mountains. During the summer rains, when great floods of water rush down the canyon, it is reported that little or none reaches the Pecos through the canyon, the greater part sinking into the arroyo bed, at one point, it is said, actually flowing into the ground through a hole. Several springs appear at various places, but they soon sink into the sand. About 3 miles from the mouth of the canyon a large and constantly flowing spring supplies a stream of water of about 7 second-feet. This may be in part the water which disappears farther up the canyon, but its constancy would seem to indi- cate some additional and more distant source. It is a clear alkaline water, which from its black color has been called Agua Negra by the Mexicans. These two streams and numerous smaller springs furnish the Pecos with a considerable body of water. At Puerto de Luna the river in early Feburary is usually 150 to 200 feet wide and 2 feet deep in places, NEWELL.] TRIBUTARIES OF THE PECOS. 285 with an average depth of one-half foot or less, and a velocity of not more than 3 feet per second. Its bed is of changing sand, and is fully 200 yards wide between the flood plain banks, showing that powerful floods must till the river at times when it overflows its banks. It is a treacherous stream, more difficult to control than even the Bio Grande. Hear Puerto de Luna it is continually encroaching on its banks, and portions of several farms have been washed away within a few years. Excepting occasional small springs from the Agua Negra and Arroyo Yeso, there are no living tributaries to the Pecos below Fort Sumner on the west side for a distance of 50 miles. The Yeso carries a small body of water of not more than 2 or 3 second-feet. Various arroyos, creeks, and springs of alkaline water flow into the Pecos between the Yeso and the Spring Biver at Boswell, but none of them are of impor- tance, few reaching the river, and these few carrying mere threads of water. At Boswell is the finest and most easily controlled supply of water in the territory, and an equally good body of land to be irrigated. There are five sources of water supply, the Pecos, the Hondo, the North Spring Biver, the Berenda, and the South Spring Biver. The Pecos is treacherous and difficult to control, and it is said never to fail even above the Spring Biver, although in summer it is often very low. The Berenda Biver is one of the Spring Bivers, all of which have their source in small ponds supplied by perennial springs. The sources of all are in the midst of the prairie, within a few miles ot each other and the Pecos. The Berenda, the northernmost of the three, had in February, 1889, a width of 12 feet, an average depth of 2| feet, and a surface velocity of 1 -9 feet per second, giving approximately a discharge of 50 cubic feet per second. The North Spring Biver rises in springs having a temperature some- what higher than the average air. At 2 p. m., February 9, 1889, when the air temperature was 59° the water temperature was 67°. The union of the streams from the several springs forms the North Spring Biver, which had at that time a discharge of approximately 50 second- feet. Both the Berenda and the North Spring rivers empty into the Hondo before reaching the Pecos, but the South Spring Biver flows directly into the Pecos, the discharge being 73 second-feet. The Hondo, formed by the confluence of numerous brooks rising in the White Mountains, flows for some distance through the foothills, and then enters the prairie country west of Boswell. Just before emptying into the Pecos it receives the water of the Berenda and North Spring rivers. In the summer above the mouth of these rivers it becomes very low and the bed even dries. In 1880 it was dry for two months ; in 1887 for three weeks; in 1888 for only one. On the prairie it flows in a tortuous course through a narrow channel, cut in loose gravel, from 8 to 15 feet deep. Float observations at Long’s Bancli, 10 miles west of Boswell on the 280 HYDROGRAPHY OF THE ARID REGIONS. Hondo, showed that the river on February 10, 1889, discharged 48 second-feet. Below the junction with the Spring rivers it carries about 200 second-feet at the point where a large ditch is to be taken out. The discrepancy of 52 cubic feet per second between the measurement of the combined- flow of the Hondo and its two tributaries and of the separate measurements is mainly due to the increase in size of the stream between the points where the observations were taken, due to the supply from numerous small springs. There are many of these in sight, and undoubtedly many which do not appear, and these swell the size of all the streams considerably. They are all alkaline and warmer than the air temperature, one of them being Gl° and another 62°. The entire absence of tributaries on the eastern side of the Pecos is very striking, and is due no doubt to the pervious character of the soil of the Staked Plains, upon which no drainage system is established. The only supply of water which the Pecos receives from this side comes from a few small alkaline springs or from a small arroyo which carries water once or twice in a season. LOWER TRIBUTARIES IN NEW MEXICO. Below Boswell the first stream of importance is the Bio Felix, which rises among the southeastern foot-hills of the White Mountains, and after a few miles sinks and does not again appear until within 4 miles of its mouth, a distance of 25 miles, where it appears again as a series of springs. The Penasco takes its rise in the Sacramento Mountains, and formerly flowed 40 miles as a fair-sized brook, then entering a strip of marshy land 10 to 12 miles long it disappeared. There was practically no con- nection between the Upper and Lower Penasco, the latter commencing in a series of springs about 12 miles from the Pecos. A few years ago a cattle company cut a ditch connecting the Upper and Lower Penasco, and since then there is a continuous stream with water running 30 miles farther than formerly. The Seven Bivers are seven small springs in the prairie, from each of which a small stream flows for a short distance, then sinks. About 35 miles below Seven Bivers is the Black Biver, which drains a portion of the eastern slope of the Guadalupe Mountains. It is larger than the Berenda, and carries an unfailing supply of water. This river is about 35 miles long, but is a small stream to within 16 miles of the Pecos, where its volume is considerably increased by numerous springs. It flows through a series of lakes, and is subject to extensive floods on account of the large area which it drains. A small stream, the Blue Biver, flows into the Black Biver a few miles from its mouth. The Delaware is the last stream to enter the Pecos in New Mexico, only about 7 miles being in this Territory. It is larger than the Berenda at Boswell. From this brief description it will be seen that the constant, never- NEWELL.] IRRIGATION ON THE PECOS. 287 failing supply of water in the Pecos cpmes from springs which must receive their supply from a great distance. This is owing to the pecul- iar structure of the country and the prevalence of the easily dissolved limestones, which allow the waters to make underground channels for themselves and thus How for considerable distances out of sight. The melting snows and summer rains furnish a variable supply which fills the channels and frequently overflows the flood-plains of the Pecos and its tributaries. The river is alkaline on account of the character of the springs. No silt is received during a portion of the year from any tribu- taries except the Hondo and possibly the large streams south of it, yet the Pecos is muddy to an extreme, being busily employed in removing a portion of the mud brought down the arroyos in vast quantities after every rain. AGRICULTURE ALONG THE PECOS. The agriculturist who needs the water of the Upper Pecos River for irrigation finds himself confronted by almost insurmountable difficulties. Even the patience of the Mexican is exhausted by the freaks of this stream, and his brush dams are certainly not a success. Above Anton Chico the Mexicans succeed in irrigating small patches of land, but all their methods are crude and their results are unimportant. Below Anton Chico all the irrigation is in the hands of Mexicans as far south as Fort Sumuer. A short distance north of Anton Chico a few Mexicans succeed in raising occasional crops of oats and corn with- out irrigation, but farming on this plan is not a success there. At Whitmore’s ranch are the (f allin as Springs, which boil up through the clay and discharge altogether 2 or 3 second-feet, the water being used to irrigate a small farm by storing that which flows during the night to aid the supply by day. There is a large extent of valley land in this neighborhood at present uncultivated on account of the uncer- tain supply of water in the Gfallinas River, which is frequently dry in the growing season. From Gallinas Springs nearly to Las Colonias the river flows through a canyon with some irrigable land on either side. Above Las Colonias the canyon broadens until the walls, which are 200 to 300 feet high, are fully 2 miles apart. From the base of these cliffs on either side to the river the land is capable of irrigation, although the Mexicans have reclaimed only the narrow strip bordering the river. By the end of August the water fails in the river at this point, and there is little if any in it again until about April. On the east side some of the rich bottom lands are capable of raising a poor crop of corn without irri- gation, owing, no doubt, to seepage from the river. Below Las Colonias the canyon walls come closer together, and there is no irrigable laud for 15 miles, or until Agua Negra Springs are reached. Here the valley broadens out again to a width varying from one-half mile to 2 miles or more. From this point southward the valley contracts and broadens out again at varying distances until the canyon country is left behind a few miles above Fort Sumner. 288 HYDROGRAPHY OF THE ARID REGIONS. On the Pecos and Gallinas rivers north of Puerto de Luna about one- half of the easily irrigable valley land is under cultivation, but in all this region nothing has been done in the way of permanent improve- ment ; no trees are planted, few vines, and very little alfalfa. Either the Mexicans are not thrifty, or else they are afraid to run the risk of losing trees and vines by drought and bursting of dams. IRRIGATION WORKS ON THE PECOS. The town of Puerto de Luna, a Mexican town, is divided into two parts by the Pecos. The western town has a very good acequia taking most of the water of the Agua Negra, and thus possesses a constant supply. All the water is utilized on small Mexican farms, each a few acres in extent. On the east side of the river many unsuccessful attempts have been made to take water out of the Pecos after the usual Mexican method, and even the Mexicans are convinced that the Pecos is entirely too changeable and violent a river for brush dams. A ditch 4 miles in length has been constructed, and four times the dam has been swept away, leaving the irrigators without water in the midst of the season. The last dam was built in the autumn of 1887, at which time a road was built to the mesa top for brush, aud several thousand dollars in labor were expended in constructing the dam, which was swept away in the spring. The inhabitants are reduced to extreme poverty and are in despair. In 1888 and 1889 they were entirely with out water, and, as it did not rain during the summer, those who tried to raise crops without irrigation made complete failure. The only man who had fruit trees was forced to irrigate them by carrying water in pails. Between Puerto de Lima and Roswell little land is irrigated. Puerto de Luna is practically the limit of Mexican advance, though below there an occasional Mexican farm is found, irrigated either by a small private acequia or by spring water. At Roswell more land is cultivated, but the proportion of irrigated to irrigable land not irrigated is very small. Between Roswell and the Texas line, including the country about Roswell, there were in 1889 not more than 3,000 or 3,500 acres of land under cultivation on both sides of the river. In this tract of country there are 300,000 acres of land that can easily be reclaimed. Within a radius of from 2 to 3 miles from Roswell there were in 1889 less than 2,000 acres of cultivated land, including about 300 acres of alfalfa, 40 acres of fruit trees and vines, and 50 acres of timber planted under the timber-culture act. The amount of cultivated land is increasing rapidly each year, and especially in the last few years there has been great activity in ditch construction. The following statements of the carrying capacity of the various acequias about Roswell in 1889 were furnished by the con- structing engineer, the estimates being based upon the number of acres that each ditch could flood to a depth of 18 inches during the irrigat- IRRIGATION DITCHES AT KOSWELL. NEWELL.] 289 ing season, taking into account the watgr supply, character of the land, and size and slope of the ditch : From Berenda River: Boon Ditch Milne Ditch Crow Ditch From North Spring River : Ballard Ditch Pioneer Ditch Stone Ditch Roswell Ditch From Hondo River, Fountain Ditch From South Spring River : East Sea Ditch Corn Ditch Mills Ditch Poe Ditch Roberts Ditch South Sea Ditch Acres. 40 100 150 300 700 1, 500 0 ) 20 150 200 300 300 1,500 2,000 When all these ditches were running to their full capacity about one- half the water was taken out of the Berenda, while tlie amount taken Fig. 225. — An acequia at Boswell, New Mexico. from the North Spring River did not appear to be materially decreased, and in the South Spring River very little water was left. The Berenda at its headwaters is a small stream, and possibly the carrying capacity of the first three ditches has been underestimated. A vieiv of one of these small ditches is given on Fig. 225, showing the general character of these acequias and the regulating gate at the head. These regulating gates, as previously stated, are of wood, roughly made, all such works being constructed by the irrigators. On 12 geol., px. 2 19 Supplies the town. 290 HYDROGRAPHY OF THE ARID REGIONS. the left-hand .side of the picture are stacks of alfalfa, which has been raised by means of the water of the ditch. There is nothing unusual in the general appearance of this ditch, and the picture is introduced merely to show the general character of the country, since it might have been taken almost anywhere in the Rio Grande Basin. Since 1889 several large irrigating systems have been laid out and in part completed along the Lower Pecos in New Mexico, and even extending into Texas. The most notable is that in the vicinity and south of the town of Eddy, where a masonry dam located a few miles above the town serves both to divert the water into the canals and to a certain extent to impound the floods. These canal systems have been described in great detail in various publications, 1 rendering it unnecessary at this time to enter into a description of them. The storage of surplus water is a matter of great concern to all these canal companies and irrigators, and a number of favorable reservoir sites have been surveyed and plans have been drawn tip for extensive works of this character. DRAINAGE BASIN OF THE COLORADO RIVER. This great river, draining an area of 225,049 square miles and deliv- ering a great volume of water into the Gulf of California, has within its catchment basin the most diversified and wonderful topography on the continent. The Grand and Green Rivers, rising in Colorado, Wyoming, and Utah, receive their waters from the western side of the Rocky Mountains and from the Wasatch and Uinta ranges. Uniting their floods to form the Colorado, they flow through the most stupen- dous canyons of the world, from 3,000 to 0,000 feet in depth below the tops of the plateaus, into which the tributary streams also have cut gigantic gorges. After leaving the canyons the stream meanders through the broken lands and deserts south of the Great Basin, and shortly before reach- ing the Gulf of California receives at Yuma the waters of the Gila River, which drains southern Arizona and a part of New Mexico, and whose basin is described in detail farther on. On PI. lxxiv are given the fluctuations of the river at Yuma for each year since 1880. The dotted line indicates the average height ot the river during the entire period through which measurements have been made, and the irregular line indicates the stage of water during the particular year whose date is affixed to the left side of the dia- grams. An examination of these diagrams shows that in the year 1880 the height of the river was in general below the average, rising above this only for short periods and quickly falling. In 1881 and 1882 the 1 Notably by H. M. Wilson, in tlie Engineering News, New York, October 17, 1891, ami also in pamphlets issued by the Pecos Irrigation and Improvement Company, Eddy, New Mexico. LIBRARY OF THE UNIVERSITY Of ILLINOIS U. S. GEOLOGICAL SURVEY Jan. Feb. Mar. Apr. May. June. July. Aut. Sept. Oct. Nov. Dec. GAUGE HEIGHT OF THE COLORADO TWELFTH ANNUAL REPORT PL. LXXIV Jan. Feb. Mar. Apr. May. June July. Aug. Sept. Oct. Nov. Dec. CP AT YUMA, ARIZONA, 1880 TO 1891. NEWELL.] DISCHARGE OF COLORADO RIVER. 291 height followed the normal very closely, and iu 1883 was for a great part of the year a trifle above. In 1884 floods of unusual extent occurred; in March the water was higher than it had beeu for many years, and in the latter part of May, during June, and the first half of July the floods were unprecedented both in amount and duration. Throughout the western part of the con- tinent this year was notable for the excessive rainfall and height of the rivers, and even in the subhumid regions the rainfall was so great that settlement was encouraged in localities where no crops have been ma- tured since that year. By referring to the diagram of annual rainfall in the Rio Grande Basin, Fig. 223, and of that of the annual rainfall in the Gila Basin, Fig. 226, it will be seen that in nearly all the localities whose rainfall is plotted the depth of precipitation in 1884 exceeds that of the years immediately preceding or succeeding. In 1885 the river was in general below the normal height, and in 1886 was at nearly the same stage, the June flood being larger than in the preceding year. In 1887, 1888, and 1889 the river remained at or below the normal, the June flood of the latter year being so small in compari- son with that of March as barely to show an increase. In 1890 the water remained above the normal for the whole year, but the June flood, which promised to be so large, dropped off abruptly in the middle of the mouth. The spring of 1891 was characterized by the greatest flood of which a record has be6n kept. This came, as have most of those of February and March, from the Gila Basiu, where a large amount of damage was done by the extraordinary rains. This sudden flood is interesting from the fact that it was probably the cause of the submergence of a portion of the Colorado Desert in the central part of San Diego County, Cali- fornia. The lowest part of this desert, at a point about 60 miles west of the Colorado River, is 225 feet or more below sea level. The South- ern Pacific Railroad runs through this depression, and the unexpected appearance of the water at this remote point occasioned some alarm and also damage to the salt works on the lowest ground. Discharge measurements of the Colorado River were made by the Wheeler Survey in 1875 and 1876 at three points — Stone’s Ferry iu Ne- vada, below the mouth of the Virgin, at Camp Mohave, Arizona, and at Fort Yuma, California, the results of which are given in a memoran- dum by Lieut. Bergland. 1 At Stone’s Ferry the measurements on August 12, 1875, gave the area of section as 5,723 square feet, width 480 feet, mean velocity 3*217 feet per second, and discharge 18,410 second-feet. The high-water mark of 1871 Avas 17*01 feet above surface of water at the time of obser- vations. Increase of area at high water Avas 9,773 square feet. The 1 Annual report upon the geographical surveys west of the 100th meridian iu California, Nevada, Utah, Colorado, AVyoming, New Mexico, Arizona, and Montana, by George M. AVlieelor, first lieuten- ant of engineers, U S. A., being Appendix JJ of the annual reportof the Chief of Engineers for 1876, pp. 71-72, 119-125, AVashington, 1876. 292 HYDROGRAPHY OF THE ARID REGIONS. whole discharge at that time takes place through the section. Assum- ing the mean velocity to remain the same as on August 12, 1875, the in- crease in discharge would be 31,440 second-feet; but as in reality there would also be an increase in the velocity, the increase in discharge would be somewhat greater than this. At Camp Mohave on September 2, 1875, the area of section was 4,628 square feet, width 1,110 feet, mean velocity 2-508 feet per second, and discharge 11,011 second-feet. The high-water mark of 1874 was 8 feet above surface of river on that date. The increase of area of section at high water, excluding overflow on flats, would be 13,656 square feet, and the increase in discharge through the section would be 34,274 sec- ond-feet, but as a considerable quantity of the bottom beyond the sec- tion is then covered with water, this will not represent the total increase. At Fort Yuma on March 20, 1876, the area was 2,726 square feet, width 461 feet, mean velocity 2-809 feet per second, and discharge 7,659 second-feet. The high-water mark of 1862 was 10-19 feet above the sur- face of the river. The increase of area of section at high water would be 5,059 square feet. The increase in discharges through section would be 14,244 second-feet. Here the velocity throughout the section would be increased at time of high water, and a large quantity would flow outside of the section, since the bottom lands would be flooded. Adding the iucrease of discharge, due to the increase of area, to that measured, the flood discharges at the three places would be at least 49,850, 45,885, and 21,903 second-feet, respectively, to which is to be added the amount passing outside the sections, which in the case of Fort Yuma is large. It is stated that the computed increase for Camp Mohave is probably nearer the truth than that for the other localities. THE GILA BASIN. TOPOGliAPIIY AND ALTITUDES. The Gila Basin (PI. lxxv), the most southerly portion of the great Colorado drainage basin, includes the greater part of Arizona, as well as a portion of New Mexico and of Sonora, in the Republic of Mexico. In all this area of 66,020 square miles the success of agriculture depends upon the artificial application of water to the crops. This water is de- rived from the Gila River and its tributaries by means of canals and ditches, which distribute it to the fields of each farmer. These streams fluctuate greatly, being at times subject to sudden floods, especially during summer rains, when they often sweep out bridges, dams, and canal head works, while at other times they may diminish until the water almost disappears. In floods there is, of course, far more water than can be used, although at this season as much as possible is put upon the crops, especially the forage plants, and great quantities are turned upon the fields in order to saturate the ground; but, on the other hand, during the ordinary low stages of the streams, the acreage of crops is limited to that which can be watered by the diminished flow. j [^trrrpn S (IKOI.OC.K-Al, SURVEY TWELFTH ANNUAL, REPORT. FART II PI, LIBRARY OF THE UNIVERSITY OF ILLINOIS NEWELL.] TOPOGRAPHY OF GILA RASIN. 293 On PI. lxxv is given a map of the basin on a scale of 40 miles to the inch, with contour interval of 1,000 feet. This is taken from the U. S. Geological Survey map of 1891 and shows in a general way, as is necessary on this scale, the elevations in this basin. It has been de- rived from all material accessible and gives at a glance the present condition of our knowledge of this important region. By glancing at this map it will be seen that the high land of the basin, as indicated by the darker color, is along the northeastern edge. By consulting the full map from which this is taken it would be seen that this rim of the basin is not composed of high mountain ranges, as might appear from the small map alone, but is really the edge of a great plateau. Against the edge of this great plateau the prevailing winds from the south or southwest strike, and, being forced upward, as they rise deposit their moisture in the form of rain or snow, which, rolling backward, forms the small streams that, uniting, feed the Gila. The map shows these little streams flowing in a general southwesterly direction and in the northern part of the basin uniting to form the Verde, which flows southerly parallel to the face of the cliffs. A- little farther to the south and east these streams unite in the Salt, which also flows very nearly parallel to the edge of the drainage basin, but to the west to meet the Verde. On the extreme eastern edge of the basin the plateau-like character gives place to mountain ranges, and a less regular arrangement of the small tributaries is found there. They flow in almost every direction, to unite finally in the Gila, which takes a course nearly parallel to that of the Salt. The remainder of the rim of the basin is poorly defined. The eleva- tions are lower, and consequently the precipitation is less, and, with little rainfall, the streams are small, and seldom extend sufficiently far from the mountains to unite into a perennial river. Most of them sink into the broad, sandy plains soon after leaving their canyons; and while from the considerations of the topography they may be consid- ered as belonging in the drainage basin of the Gila, yet they seldom or never contribute to its waters. Thus the drainage basin of the Gila may be considered as consisting of two great divisions — that on the northeast, shown on the map by the heavy tints, rugged and precipitous, catching the moisture from the clouds; and that to the southwest consisting principally of vast areas of nearly level land, shown in lighter tint, much of it exceedingly fertile, and in every way adapted to agriculture, excepting in the one particular, the lack of water. Were it not for the position of these high plateaus, all of this fertile land would remain forever valueless to the farmer, and thus it is that the mountain region, even if it were of no other use, would still be valuable as a collector of rainfall. This great area, however, is not wholly useless, for much of it is valuable mineral land, the mines from which have brought prosperity to parts of the basiu. 294 HYDROGRAPHY OF THE ARID REGIONS. Assuming that this map of the drainage basin is approximately cor- rect, sufficiently so for general purposes, computations have been made of the area of land lying at different elevations, the results being as follows : The total area of the basin is 60,020 square miles. Of this area — 9 per cent is under 1,000 feet. 19 per cent is between 1,000 and 2,000 feet. 16 per cent is between 2,000 and 3,000 feet. 14 per cent is between 3,000 and 4,000 feet. 15 per cent is between 4,000 and 5,000 feet. 12 per cent is between 5,000 and 6,000 feet. 8 per cent is between 6,000 and 7,000 feet. 7 per cent is over 7,000 feet. The greater portion of the land lying at an elevation of less than 3,000 feet, may be classed as sandy plains, in large part agricultural if water could be supplied ; in other words, about 44 per cent of the entire area of the basin would fall into this class. The lands over 5,000 feet in ele- vation may be considered as mountainous catchment areas. These ag- gregate 27 per cent of the entire basin, and it is from this 27 per cent, or a portion thereof at least, that all of the water comes. The greater part, if not all, of the grazing and mining regions are included within this 27 per cent, as well as all the timber. The land from 3,000 to 5,000 feet above the sea is partly plain and partly foothill. A small part is agricultural, especially at the headwaters of the Verde and those of the Upper Gila, but in the main it is broken country, of little value even for grazing. In this connection it is important to note the political divisions which have been made in the drainage basin, for much of their prosperity depends upon the wisdom and foresight with which the boundaries of States and counties have been laid out. This is particularly the case in the arid regions, where the one thing of value is the water, and where the land takes its value only from its position as regards the water supply. If the boundaries of States and counties had been made to coincide with natural divisions, so that the streams with their head- waters would lie in one grand division, the future control and manage- ment of the water would be comparatively simple; but in the cases (which are unfortunately too common) where, for example, the head- waters of a stream are in one State and the irrigable land in another, there is constant strife, or even an abandonment of great natural re- sources. The Gila basin includes, besides the greater part of southern Ari- zona, a small portion of the Territory of New Mexico, and the State of Sonora, in the Republic of Mexico. In the case of this latter country the rim of the basin has been arbitrarily assumed, as there are no available maps which define it, and on the southwestern edge the boundary between the United States and Mexico is taken as the limit of the basin. This area, by counties, is shown in the following table : NEWELL. ] AREA OF GILA BASIN. 295 Square miles. Socorro County, New Mexico 3, 893 Sierra County, New Mexico 156 Grant County, New Mexico 2, 818 6, 867 Republic of Mexico Apaclie County, Arizona . . Graham County, Arizona . Cochise County, Arizona.. Gila County, Arizona Pinal County, Arizona Pima County, Arizona Yavapai County, Arizona . Maricopa County, Arizona Yuma County, Arizona 1, 168 2, 550 6, 152 6, 004 3, 212 5,300 10, 596 9, 685 9, 815 4, 671 57, 985 Total 66,020 Nearly 88 per cent of the entire area is in Arizona, a little over 10 per cent in New Mexico, and nearly 2 per cent in Mexico. By a glance at the map, PI. lxxv, it will be seen that the Gila River proper rises in southwestern New Mexico, near the Arizona line, and Hows southwesterly through Arizona to its confluence with the Colo- rado River. Its total length from the source in New Mexico to the junc- tion with the Colorado River, not including its many windings, is fully 500 miles. Besides the main Gila, the principal tributaries and streams of the basin are the San Pedro and Santa Cruz rivers on the south, and the Salt, Verde, Agua Fria, and Hassayampa rivers on the north. The hoods of the Gila are usually short and violent, the highest water occurring during the months of January and February. During a freshet the river rises in some places from 8 to 12 feet, and increases in width from 300 feet to a mile and a half. It is sometimes impassable for weeks, and has the appearance in places of a sea of muddy water. The season of low water occurs during the months of June and July, the riverbed being then dry in places. AGRICULTURAL LANDS. The aggregate area in this basin on which crops were raised by irri- gation in the year ending June 30, 1890, was found by the Census Office to be 01,857 acres, or 90-05 square miles, this land being along the main river and its tributaries, principally near the foothills, or among them wherever the valleys opened out, leaving room for Hood plains. This is between one and two tenths of 1 per cent of the entire area of the basin, or, as the land is principally under 3,000 feet in elevation, is about three- tenths of 1 per cent of this latter class. But in addition to the lands on which crops were raised there is estimated to bean acreage fully twice as large under irrigation, that is, to which water has been brought and perhaps applied in certain years or seasons, but upon which crops were not matured in the census year, owing either to scarcity of water or the undeveloped state of the country. 296 HYDROGRAPHY OF THE ARID REGIONS. It is evident from previous statements that this acreage under irriga- tion is but a small percentage of the total amount which, with ample water, might be cultivated; in fact, this latter total is so large, so much beyond the possibilities of water supply, that estimates as to its extent have little or no practical value. It is sufficient to know that there are in the Gila basin at least 10,000,000 acres of fertile soil, the greater part of which is without water. In other words, the soil and climate are favorable to an expansion of agriculture, which is limited only by the water supply. Not only does the basin possess .all the elements of sucessful agricul- ture, but it has the advantage of local markets and a constantly increas- ing demand for the products. The mining regions call for all kinds of food stuffs and forage, and, in fact, many grades of ore depend for suc- cessful handling upon a small reduction in cost of living, and conse- quently, of wages of the miners. There is thus a close interdependence between agriculture and mining, the prosperity of the one reacting upon the other; large crops increase the possibility of working the minerals, and the more laborers there are at the mines the greater is the demand for all kinds of produce.. In this connection it is interesting to note the relation which now ex- ists between the area of the catchment and the area upon which crops have been successfully raised, that is, for which there has been an ample water supply. It is impossible to obtain, without better maps, the exact area of catchment, but assuming for purposes of comparison that it lies above 5,000 feet in elevation, it is found that for every acre irrigated there are in round numbers about 180 acres of catchment area, or for every 1,000 square miles of catchment crops have been raised on a little over 5 square miles. This obviously is a very small ratio, and progress will constantly tend to increase it rapidly at first, and then more and more slowly. DUTY OK WATEK. This relation between the area of catchment and area cultivated de- pends directly upon the average duty of water, which, taking the basin as a whole, is very small, although there are instances to show that it can be greatly increased. Calculations have been made that with ordinary care and economy a second-foot should serve 120 acres. It is probable, however, that it will take some years of experience before a majority of the farmers can successfully accomplish this, and more or less hardship may arise in attempting to carry out such economy. Complaints are now made by the farmers that the larger canal com- panies do not furnish them sufficient water, while the canal superin- tendents assert that far more than a sufficient amount is allowed. An approximation of the duty of water in the Gila Valley can be made by knowing the amount which enters through the canyons as com- pared with the crops irrigated. Eliminating the floods, it lias been NEWELL.] WATER DITTY IN THE GILA BASIN. 297 found, for example, by the hydrograpliers of the Geological Survey that about 200 second-feet passed through the buttes above Florence during the year in which, as ascertained by the census, there were about 6,600 acres of crops successfully irrigated. This would give a water duty, measuring the water in the river, of only 33 acres, but it should be noted that a great quantity of this water was wasted, and was used on lands on which crops were not matured. On the lower Salt the measurement of the average How, deducting the Hoods, for this time was about 600 second-feet, and about 30,000 acres of crops were raised, giving a water duty of 50 acres. This water duty is also very low, from reasons similar to those given above, but is higher from the fact that the canals were distributed /dong a greater distance, and much seepage water returned to the river to be used a second time. Some conception of the average How of the streams of the basin may be obtained by knowing the acreage of crops successfully irrigated, assuming as correct the statements of the irrigators that these crops demanded all the water available in the streams during the time in which they were maturing. Since there were in the basin 61,857 acres irrigated successfully, it follows that with a water duty of 50 acres to the second-foot the available water supply was at least 1,237 secoml- feet, or with a water duty of 30 acres to the second-foot, was 2,062 second-feet. After the water duty has been increased to the greatest possible amount and the limit in this direction has been reached, there must be vast areas suffering for water. Under present methods, as much water as possible is turned out upon the ground in time of Hood in order to produce complete saturation and great quantities are used upon the alfalfa and other forage crops. Then, as the rivers fall, water is em- ployed to mature the cereals and vegetables, and finally during a drought the available supply is concentrated upon perennial plants, letting others perish in order to save vines, fruit and shade trees. There thus arises in this method of progress without water storage a condition of affairs in which the acreage under cultivation adjusts itself to the average perennial supply. In other words, the amount of land on which crops can be raised will be that which the river in an ordi- nary year will supply with water. If less comes than usual, a portion of these crops must burn under the heat of the sun; if more than usual Hows, a larger acreage will mature, and more cuttings of the hay crop can be made. It may be said for the Gila Basin, as well as for the greater portion of the arid region, that this condition has nearly taken place. The acreage of crops planted each year demands all the water or even more than flows during the times when they are maturing and the need is greatest. While therefore the extent to which irrigation can increase without water storage can not be satisfactorily estimated, it is apparent that this can not be very great. Every irrigator looks forward to the per- 298 HYDROGRAPHY OF THE ARID REGIONS. lection of water storage as the only method of relief from present un- certainties and losses. WATER STORAGE. In this basin a number of excellent sites are known to exist; two in particular have been so often discussed that it is sufficient merely to refer to them. The first is in Pinal County, 15 miles above Flor- ence, where the Gila flows between two “buttes,” forming a canyon 200 feet or more in width, with perpendicular walls on each side. In this canyon a dam of sufficient magnitude would impound, from various estimates, enough water to irrigate a large part of the plains below. The second is at Oatman Flats, in the western part of Maricopa County. The Gila at this point flows between bluffs of limestone from 111 to 126 feet high, and at a distance of 1,195 feet from each other. There is a large storage basin above, in which, by means of a suitable dam, sufficient water could be stored during the storm floods to serve the Lower Gila Valley during the dry season. Besides these there are numerous places where dams could be con- structed and smaller bodies of water stored. It is reported that Salt River, a short distance below the mouth of Tonto Creek, passes through a box canyon with vertical sides rising to the height of 100 feet. A suitable dam built here would impound sufficient water to furnish a part of the Salt River Valley with an abundant supply. But while there is no doubt as to there being suitable localities in which water can be held, there is some question as to the quantities of water to be depended upon to fill these reservoirs annually. Each year there are short, sudden floods carrying considerable volume of water for a few hours, and at longer intervals, perhaps of three or five years, there are enormous floods, whose violence and duration is phenomenal. These latter, however, are rather to be feared than to be depended upon as beneficial. The question arises, will the ordinary floods, such as happen every year without exception, fill these storage reservoirs? Can they be depended upon, and do they always carry the requisite amount of water? This is a question, unfortunately, which is far from being answered, and the operation of the Geological Survey being carried on for such a short time, tends rather to increase the doubt than to satisfy it. The year during which the measurements were made was one of com- parative scarcity, and these measurements, as shown on later pages, do not give the great quantities of water available for storage that is popularly supposed to exist. As before intimated, it is necessary to carry on measurements of this class for several years before engineering estimates can safely be pre- pared. Thus the first steps toward water storage in this basin on any large scale, one in which a majority of the inhabitants will be con- cerned, is to continue such measurements for a sufficient number of years to determine the necessary facts. NEWELL ] PRECIPITATION IN THE GILA BASIN. 299 A study of rainfall is interesting and may yield instructive results. If the river flow varied directly with the rainfall, the matter would be greatly simplified, but, unfortunately, the relation which exists between the precipitation as measured in the rain gauges and the amount of water available is not one of direct proportion, but is influenced by so many factors that conclusions based upon the measured rainfall alone are apt to be misleading. RAINFALL. Since the water supply comes primarily from the rains, it is well be- fore describing the different portions of the basin in detail to present some of the broader facts concerning the amount and distribution of the precipitation. Compared with the size of the basin, there are but few stations at which rainfall has been measured for a long series of years, and these unfortunately are mainly in the valleys, where the precipitation is least. As a general thing, it may be said that in this basin, owing to the diversity of topography in the higher lands, the rainfall increases with the altitude, and therefore the greater part of the precipitation occurs along the northeastern edge of the basin, while out on the great plains through which the Gila flows, and where the best agricultural land is situated, there is the least moisture, the aver- age at Yuma being less than 3 inches, at Texas Hill, 4 inches; at Maricopa, 5 inches; and at Casa Grande, a little over 4 inches; while, on the other hand, near and among the mountains, or rather the slopes of the edge of the great plateau, the rainfall increases to 10, 15, or even 20 inches and over. The precipitation of this basin is given in the various publications of the Signal Service, and for the present purpose it is sufficient to present in graphic form some of the general results. On Fig. 22(5 is given the annual rainfall for seventeen stations, the amount of rainfall for each year being represented by the height of the black blocks, the diagram being similar to that for the Rio Grande Basin. Wherever a blank occurs on this sheet, it signifies that no rainfall observations were made, or that they were incomplete. In looking at this diagram, the most striking fact is the exceedingly irregular character of the rain- fall, its variation in amount at one place from year to year, and lack of coincidence for the same year for several places ; that is to say, while at one place there is less rainfall for a given year than in the year pre- ceding, for another locality there may be more. There is, however, a certain general variation which may be traced in a broad way; that is taking all of the stations for any one year, the average shows often a decided difference from that of the average of all stations for the year preceding or succeeding. In order to bring this out, the average for all stations in and adjoining the basin has been plotted, as shown in the central figure in the bottom row of the diagram. On examining this, the most notable features are the excessive rainfalls of 18G8, 1874, 1878 and 1884, and the diminished rainfalls of 1870, 1880 and 1885, 300 HYDROGRAPHY OF THE ARID REGIONS. showing a curious alternation of ten-year periods, which, however, may be regarded as coincidences. 00 00 m m oo oo m m 0 ° 00 o in oooooooooo 00 CO 00 OO 00 00 00 00 00 00 AO in 30 ” 20 ” 10 1 » mriffwnr' i r i ri «■ ' Ft. 1 WELL Ma, /COP/ ►V/A. ox I U I.J _ ■ I u tt ■ Tex H EL CaI 4 CjR/ IA//3A Be a SON JW U Ft. Yum; Mea t or > llS: v^r/J Cam >Thc ). MS h I 1 d d A 1 J lJ J 1 1 ■A Fig. 226 Diagram of annual rainfall in the Gila Basin, Arizona. U. S. GEOLOGICAL SURVEY Twelfth annual report pl. lxxvI Prescott. Elevation.5,389 feet. Fort Verde. Elevation, 3,501) feet. Fort McDowell. Elevation, 1,H00 feet. Fort Bowie. Elevation, 4,9211 feet. Fort Grant. Elevation, 4.914 feet. Yuma. Elevation, 141 feet. * ?> v Uj * Q: ^ ^ ^ 3 a. 5 5 5 5 ^ ^ ^ S *4 (r II u ^ lil § 'll ^ *0 O < Q I iii rin 1 1 rri n -rj TT 1 jj -T-r J . f_ I li ■ u XI •LJa □ i± ITI 4 inches. 3 inches. 2 in lies. 1 inch. 4 inches. 3 inches. 2 inches. 1 ini h. 4 inches. 3 inches. 2 inches. 1 inch. 4 inches. 3 inches. 2 inches. 1 inch. 4 inches. 3 inches. 2 inches. 1 inch. 4 inches. 3 inches. 2 inches. 1 inch. AVERAGE MONTHLY RAINFALL AT STATIONS IN THE GILA BASIN, ARIZONA. USftv OF i HE UNIVEHSITV OF ILLINOIS % NEWELL.] RAINFALL AND RUN-OFF. 301 The year 1884 was an unusually rainy one throughout this basin, as well as throughout a great part of the West, as previously noted, while 1885 was a year of minimum precipitation. Since those years, the average rainfall has been nearly constant, and perhaps diminishing slightly through 1888 and 1889. There is, of course, no regularity about such matters, but a study of the experience of the past is valu- able, as indicating the range through which the amount of precipita- tion has varied, and therefore through which it may alternate again. While the amount of annual rainfall is important, it does not have snch a direct bearing upon agriculture as does the monthly and seasonal distribution of the rain; in other words, a small annual pre- cipitation may be compensated for by a distribution of rainfall such that it all occurs during the months when most needed. On the other hand, a large annual precipitation may be of small use to the farmer from the greater part occurring at times when the water is not needed, and when it runs off into the rivers. PI. lxxvi shows graphically the relative amount of rainfall during the months for six different stations. This is the average of from twelve to fifteen years, 1 and while it does not represent the amount which may be expected to fall on any one month, it does show the distribution through long periods of time. The most notable feature of this diagram is the gradual decrease of the rain from February to June, the sudden increase in July and August, a second diminution in the fall, nearly, though not quite, to that of early summer, and a second gradual increase in the winter to an amount about half that of the summer. The relation between the rainfall and the amount of water which flows in the river, commonly known as the run-off, is not a matter of direct proportion, as before noted, on account of the many modifying circumstances. A rainfall of 1 inch may or may not cause a greater rise than one of half an inch, depending upon the rate at which it falls. For example, a long-continued, gentle rain may slowly saturate the ground and contribute very little to the run-off, while, on the other hand, the same amount of water falling in a sudden local storm often causes an immediate response in the streams and produces a violent flood. Although a knowledge of the rainfall can not give information as to the water flowing in a river, yet it is of the greatest value in other con- nections. In this connection PI. lxxvii, showing a portion of the drainage area of the ill-fated Hassayampa Reservoir, is introduced to exhibit the char- acteristic topography of the higher part of the Gila Basin. In the background are shown the steep slopes of the mountains, almost bare of vegetation, and from which in time of rain the . water runs immedi- ately into the gullies and canyons. This view shows the Hassayampa Reservoir shortly after it was filled with water for the first time, the 1 Charts showing the normal monthly rainfall in the U uited States extracted from the monthly weather review, with notes and tables prepared under the direction of Gen. A. W. Gieely, Chief Signal Officer; Washington, 1889. 302 HYDROGRAPHY OF THE ARID REGIONS. tops of the higher trees still appearing above the water. The vegeta- tion throughout that country is very scanty, and, as shown in the fore- ground, there is none of the smaller growth and carpet of grass so com- mon in the humid regions. UPPElt GILA DISTRICT. The headwater basins of the Gila, as shown on the map, are as fol- lows: Upper Gila, San Pedro, Verde, and Upper Salt. The Trunk ltiver divisions are the Middle Gila, Lower Salt, and Lower Gila, while the principal lost river basins are the Agua Fria, Hassayampa, and Santa Cruz, each of which will be discussed in order. The Upper Gila district or headwaters of the main Gila may be con- sidered as including that part of the basin from the highest catchment down to the buttes above Florence, excluding, however, the San Pedro. This area embraces that portion of the basin from which the most water may be supposed to come, as well as certain large bodies of irri- gated and irrigable lands. The total area is 10,930 square miles, com- prising 3,893 square miles in Socorro County; 15G square miles in Sierra, and 2,818 in Grant County — these three counties being in New Mexico; and in Arizona — 4,220 square miles in Graham County; 880 square miles in Gila County, and 530 square miles in Pinal County. The elevation ranges from 3,000 feet up to 10,000 on the highest peaks. The principal streams, besides the Gila itself, are the San Francisco River and its branches, the Gila Bonita, and the Mogollon River. The San Francisco is a perennial stream, which derives its principal supply from melting snow, and becomes very low-, although it has not actually become dry before the summer rains. The Gila in this portion of its course Hows throughout the year, and is subject to sudden and violent floods, especially during the summer season. The supply for this district is comparatively ample, and there- fore no attempt lias been made to increase it by storage. During 1889 and 1890 crops suffered greatly on account of the scarcity of water, for, judging from general report, there was less water than during the previous decade. It is probable, however, that the supply was amide for the acreage irrigated in the census year. In general, for wheat, barley and oats, water was plentiful, but late crops often suffered and were lost. In the valleys comprised within this district crops to the extent of 9,137 acres, or 14-3 square miles, were raised by irrigation in the census year. This amounts to a little over one-tenth of 1 per cent of the total area of the district. The largest body of irrigated land is in the Pueblo Viejo Valley, extending from the canyons above Solomonville westward. In this valley, besides the land under crop, there are large tracts to which water can be brought by the ditches at present in oper- ation, the names of which, as reported to the survey by Mr. T. E. Farish, in 1889, are given below. Under the head of acres is the prob- able acreage which the ditch may be made to cover. HASSAYAMPA RESERVOIR library of '• UNIVERSITY Or ILLINOIS NEWELL.] WATER SUPPLY OF SAN PEDRO RIVER. 303 Ditches and irrigable lands. Length. Covers. Length. Covers. Miles. 9 Acres. 6,000 3. 000 6, 000 6. 000 1, 500 2, 000 2, 000 Miles. 5 Acres. 2, 000 7 8 4, 500 g 5 2, 500 12 3 6 3i 000 1,000 1, 500 4 5 4 Gonzales 5 Besides the above there are two or three small private ditches, cover- ing in the aggregate about 4,000 acres, bringing up the entire acreage which could be reclaimed by ample water to 45,000 acres. In Pinal County there are three private canals between the mouth of the San Pedro and the town of Riverside, as follows : Length. Covers. Miles. 2i 1* U Acres. 480 480 320 Many of the canals given above have sufficient water at all times for the area under crop, while others are reported to be dry for a few weeks in June and July. The question of water storage, however, has mot as yet attained great prominence, as by far the greater part of the tilled lands in this basin along the river have ample water, and there are still tracts in various localities which may, with proper care and economy of water, be brought under irrigation. THE SAN PEDKO DISTRICT. The San Pedro rises in Sonora, Mexico, and flows northerly through Cochise County, a corner of Pima, and the western end of Pinal County, Arizona, entering the Gila below Dudleyville, 45 miles above Florence. This total area comprises about 2,820 square miles, of which 120 miles are in Mexico, 1,900 miles in Cochise County, 267 in Pima, and 533 in Pinal County. The limits of this district can not be accurately defined as there are no good maps of this extreme southern portion of the United States, and the outlines can be sketched only in a general manner. Eastward of this district and south of the upper Gila district is a large area of about 5,700 square miles, which has been included within the hydrographic basin of the Gila, but in which there are no large streams, whatever rainfall there is being usually evaporated before streams of any size are formed. The water supply of this basin comes almost entirely from the San Pedro River, which is perennial, but which, like all other streams of the basin, fluctuates greatly. The season of scarcity usually occurs in May and June, the rains of summer tending to swell the river in July, Au- 304 HYDROGRAPHY OF THE ARID REGIONS. gust, and September. No attempts at storage have been made, but the irrigators appreciate the necessity of so doing, and regard this matter as of first importance. The supply is considered sufficient for the small grains and hay, but for late crops of corn and beaus there is sometimes a scarcity. It is reported that there was more water in 1890 than for some years previous. The river, receiving most of its waters from a country of very light snowfall, depends for the greater part upon the showers of summer. For many miles it flows over a sandy bed between high banks. During the rainy season the waters rise suddenly, even, it is reported, to 12 feet in places, assuming then the character of a torrent, in droughts it shrinks to an insignificant stream of clear water, sinking into the sands and again reappearing, where the ground water is forced to the surface by impervious layers or bed rock. In the upper San Pedro Valley are several thousand acres devoted to stock raising, much of which can, however, be irrigated in time by a careful conservation of the waters. For a distance of over 60 miles along the river small ditches have been taken out. The soil of the val- ley is fertile, producing good crops of alfalfa, wheat, oats, barley, vege- tables, and various fruits. The following is a list of the canals, as given by Mr. T. E. Farish in 1889: Canals of San Pedro Valley. Length. Covers. Brown Miles. H Acres. 160 Cook q 200 Dodson 2 320 Puscli 2 640 Bates 14 160 Length Covers. Miles. 14 14 2 11 1 Acres. 320 320 480 480 80 Harrington In the lower portion of its course the river is in places dry, owing to the diversions made by a large number of small canals. In addition to the main stream there are in the mountains, at the outlets of various canyons, a number of small springs, whose waters have been used for agricultural purposes and which are of considerable value to the own- ers, but these do not form a notable feature in the water supply of the district. The total area upon which crops were raised in this district during the census year was 2,672 acres, or nearly 4-2 square miles, or • 0T5 per cent of the entire basin. Water storage is urgently needed, and there are unquestionably facilities for this, the great obstacle being the lack of information as to the amount of water available. Measurements of water in this basin were begun at a station near Dudleyville, to obtain the amount dis- charged into the Gila. The station was placed at this point largely from the fact that it could be operated in connection with the ganging NEWELL.] IRRIGATION NEAR FLORENCE, ARIZONA. 305 station at the Buttes, above Florence. The measurements were begun on April 9, 1890, and continued until the hydrographic fieldwork was suspended. The results are as follows : San Pedro — Dudleyville, Arizona. [Drainage area, 2,870 square miles.] Discharge. Run off. Month. Max. Min. Mean. Total for month. Depth. Per square mile. 1890. Sec. feet. Sec. feet. Sec. feet. Acre feet. Inches. Sec. feet. April 9 to 30 21 5 14 833 ■005 •005 May 9 5 6 369 •002 •002 5 1 3 179 •001 •001 July 225 1 13 800 •005 •005 August 507 102 295 18, 140 ■121 •105 •134 It so happened that the gaugiugs were made during a year when the floods were apparently small, although at a season when they were liable to occur with violence. After the work was suspended there were several periods of high water, but the quantities discharged can not be computed, as the gauge rod was injured. Judging from the reports ot residents of the valley, this was a year of minimum river flow, so that the measurements must be considered as far below the average. THE MIDDLE GILA DISTRICT. The middle Gila district is a trunk river division, and depends for its watgr supply upon the amount which comes from the two districts above mentioned, namely, the upper Gila and the San Pedro. The limits of this district are somewhat arbitrary, the district being con- sidered as extending from the Buttes above Florence to the junction of the Gila with the Salt, and including on both sides of the river that portion of the great plain which can be irrigated from the Gila River. There were in this district 6,619 acres of crops irrigated, as shown by the census of 1890. The water supply for this land comes wholly from the Gila River, and the development of agriculture within the district de- pends upon the conservation and economic employment of this water. In the latter part of June the bed of the river is often dry, its water being diverted by the numerous canals of this district. Floods are lia- ble to occur with great violence in July and August, as well as in Jan- uary, February, and March. There is usually sufficient water to ma- ture one crop, but it is reported that the second crop has been lost repeatedly. According to the statements of the irrigators, the year 1890 was one of the dryest known, while during 1889 the supply may be considered as about at^an average. In the Middle Gila Valley, beginning just below the canyon, 12 miles above Florence, the following canals were reported by the hydrographers as taking water from the river in 1889 : 12 geol., pt. 2 20 306 HYDROGRAPHY OF THE ARID REGIONS. t'anals of the Middle Gila Valley. Length. Covering. Length. Covering. Moore’s Miles. 3 . 1 cres. 300 Miles. 6 Acres. 1, 000 1,000 1,000 1,000 1,000 200 McClelland 3 300 Sharp 3 160 7 Stiles 4 300 4 9 200 4 Brash 4 400 3 Florence 43 20, 000 3 300 The amount of water available for this basin was accurately determined by the Geological Survey during about one year; but their work was stopped at the end of this time by lack of further appropriation. The gauging station was established at the Buttes, about 15 miles above Florence, at a location well known from the favorable advantages which it offers for the storage of water. Here measurements were made from August 26, 1889, to September 1, 1890, the results of which are given in the following table, and are shown graphically on PL lxx vm. According to the statements of men who have been for some years in that district, the water supply of that year was lower than usual. This assumption, however, will not hold if diversions of the water continue to be made in the Upper Gila district, where there is still a large acreage of good arable land to be brought under cultivation. Gila River, Buttes, Arizona. [Drainage area, 15,370 square miles.] Discharge. Total for month. Eun off. Month. Max. Min. Mean. Depth. Per square mile. 1889. Aug. 26-31 Second-ft. 124 Second-ft. 110 Second-ft. 115 Acre feet. 7, 072 Inch. •008 Second-ft. ■007 210 90 128 7,616 9, 655 *009 •008 210 140 157 *014 •012 250 156 212 12i 614 16, 912 41, 820 32, 079 23, 800 14, 161 5, 350 1,666 7, 995 *015 *013 890 124 275 •020 •018 1890. 2, 100 1, 514 710 310 680 •051 •044 405 578 •039 •037 300 387 •029 •025 333 158 238 •017 •015 150 35 87 •007 •006 35 27 28 •002 •002 3, 112 11 130 •009 008 6, 330 1,115 3,137 192, 925 •235 •204 6, 037 503 366, 593 •447 In the latter part of the above table is given the depth of the run- off in inches, and it is of interest to note the small amount of this and the relation between it and the depth of rainfall as measured at various points in and near the basin. In the following table the depths of precipitation is given as pub- lished in the reports of the Signal Service for the months during which DAILY DISCHARGE OF THE GILA RIVER AT THE BUTTES, ARIZONA. TWELFTH ANNUAL REPORT PL. LXXVIII LIBRARY OF THE UNIVERSITY OF ILLINOIS NEWELL.] RAINFALL IN THE GILA BASIN. 307 tlie river gaugings were made, and at the bottom is the mean of the depths of the stations reporting. If it be considered that this in a general way represents the average for the basin, or at least varies with the average rainfall in the basin, a comparison can be made between the rainfall and run-off. The heavy rains of September do not appear to have had an immediate influence on the river. On the other hand, the decreasing rainfall in September, October, and Novem- ber is accompanied by a gradual increase in discharge of the river, indicating that while the precipitation may be less in amount, yet, as winter approaches the showers may have a greater and greater influ- ence on the river discharge. Comparing the tota l of the monthly mean precipitation — 15-50 inches — with the total depth of run-off for the year — 0.447 inch — it appears that a little less than 3 per cent of the rainfall of the basin reaches the gaug- ing station, under the assumption that this average of the measured rain- fall represented that for the entire basin. If no diversions of water for irrigation had been made in the upper Gila and San Pedro districts, this percentage would have been larger, reaching possibly as high as 5 per cent. It is to be noted that over one-half of the run-off of the en- tire year came in August. Monthly precipitation at station s in and adjoining the Gita Basin, in inches. Station. 1889. 1890. Sept. Oct. Nov. Dec. Jan. Feb. Mar. Apr. May. June. July. Aug. Bisbee 3-79 0-38 0-20 0-29 2-34 0-20 0-24 015 000 0-03 6-07 5-71 0-58 1 11 T 012 1-28 0-08 0*95 o-oo 0-03 3-90 5-07 Dragoon 0-18 1-55 0-78 o-oo 0-82 0- 97 1- 88 2-11 1*63 0*43 1-46 000 052 0-32 0-75 T o-oo o-oo T T 4-09 4-73 Fort hayartl 2-19 0-67 o-oo T 1-40 T Oil o-oo 4-17 3-86 Fort Bowie 2-79 0-74 T 0-57 0-78 0-23 0'03 0-59 o-oo T 4-97 4-0t> Fort Grant 0-69 0-94 0-16 1-11 1-58 0-4G 0-46 0-92 o-oi 0-20 3-24 4-54 Fort Huachuca 2'4« 004 0T4 0-75 1-50 010 T 0-34 o-oo o-oo 4-38 4-49 Fort Thomas 0-38 026 0-34 1-18 1-92 0-49 0-45 1-21 o-oo T 202 411 252 0-04 o-oo 0*90 0-75 015 0-79 o-oo o-oo 2-49 630 San Carlos 213 0-97 0-71 1*17 0-50 0-83 2-05 523 210 3-77 1*40 293 0-88 064 1- 31 2- 63 0-00 o-oo 000 2-25 3-26 Teviston 230 0-60 0-20 0-20 3-80 T 0-20 3-00 o-oo o-oo 5-20 4-00 Wilcox 2'79 0-80 0-02 0-50 1-61 0-35 0-11 0-63 o-oo 0-15 2-64 5-20 Mean 1-80 0-63 0-23 1-13 1-98 0-67 0-27 0-97 o-oo 0-03 3-24 4-61 Runoff 0-009 0-014 0015 0-020 0-051 0-039 0-029 0-017 0-007 0-002 0-009 •235 Per cent 0-5 2-22 6-5 1-7 2-57 5-82 10-7 1-7 o-oo 6-6 2-7 50 The most important question is as to how much water could have been saved during this year, if a suitable dam had been at this place. It is evident that not all the water could be held; a certain amount must be allowed to flow down the channel for the ditches below. It is also necessary to assume that there would be a constant loss of water by evaporation. The measurements of this factor have not been continued for a time sufficiently long to give a large range of results, but from an examination of these and other data the following rate has been assumed in round numbers: 308 HYDROGRAPHY OF THE ARID REGIONS. Loss by evaporation from a water surface. January . February March - ' - April May June July Month. Quantity. Mouth. Quantity. Inches. Inches. 3 August 13 4 September 10 6 ( Ictober 6 7 November r 10 11 December 4 12 Total 91 In order to obtain general ideas concerning tlie amount of water which could have been stored during the year in which measurements were made, one or two examples may be given, taking different rates of outflow for the various months. For any given acreage under culti- vation a certain amount of water must be allowed to flow in the river all the year round, less being needed in winter than in the heat of sum- mer, but some being used even in the former season, especially on for- age crops. These examples are placed in tabular form for convenience. In the first case it is assumed that no water is held during September, October, and November of 1889, but that in December, January, and February only 150 second-feet are allowed toflow in the river; in March, April, and May, 250 second-feet; in June, July, and August, 300 second- feet. The first column gives the months. The second column the average inflow of the supposed reservoir in second-feet; that is, the measured amount of water flowing in the river. The third column gives the amount assumed to be discharged steadily from the reservoir. The fourth column gives, in round numbers, the loss by evaporation in acre- feet, making certain assumptions as to the size of the reservoir and con- sequent area of surface exposed to evaporation. The fifth column gives the amount of water which is left in the reservoir at the end of each month. Mouth. Iuflow. Outflow. Evapora- tion. Bal. at end of month. 1889. Sec. feet. ' 128 See. feet. Acre-feet. Acre-feet. 157 212 275 150 100 7,400 1890. 680 150 500 39, 760 62, 728 578 150 1,000 387 250 2, 000 69. 222 238 250 2, 000 66. 502 May 87 250 3, 000 53. 396 28 300 2. 000 35. 076 July 130 300 2, 000 22, 536 3, 137 300 4,000 193, 036 In the second case, all of the water being allowed to flow during Sep- tember and October, 200 second -feet is discharged into the river during November, December, January, and February, and 250 second-feet in March and April. This amount is then increased to 300 second-feet in DAILY DISCHARGE OF THE SALT RIVER ABOVE PHENIX, ARIZONA. 5 X January. February. March. April. May. June. July. August. September. October. November. December. 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 library OF THE UNIVERSITY OF ILLINOIS NEWEI.I.. 1 WATER SUPPLY FOR STORAGE. 309 May and 350 in June, July, and August, leaving a balance at all times in the reservoir as shown in the fifth column. Month. Inflow. Outflow. Evapora- tion. Bal. at end of month. 1889. Sec. feet. 128 Sec. feet. Acre-feet. Acre feet. 157 9.12 200 700 275 200 80 5. 230 1890. 680 200 400 34, 330 54, 320 00, 760 58, 045 42, 445 21, 295 578 200 1, 000 2, 000 2.000 387 250 238 250 87 300 2, 500 28 350 2, 000 1, 500 130 350 6, 275 3,137 350 4,000 170, 275 The amount of land which would be irrigated by the streams which have been assumed in these examples as coining from the reservoir will vary largely with the character of crop, especially the proportion of forage plants, these requiring water at all seasons. A conservative estimate, however, of 75 acres to the second-foot will probably cover all contingencies. This duty, as is recognized, is small, from the fact that the water is returned to the river from the reservoir and is not taken directly by short canals upon the land. In the first case assumed in these examples of a flow of 300 second-feet in June, July, and August, at least 22,500 acres can be covered, and in the second case, with a larger percentage use of water during the winter, 26,250 acres can be irrigated. These examples and an infinite variety of others which might be taken, using different combinations of figures, merely serve to show that even in a dry year sufficient water can be held to protect a large acre- age and render irrigation a matter of certainty. Other engineers, in figuring the amount of water available, will undoubtedly take other values, and in most cases they will estimate that a far larger acreage can safely be covered, since these examples are taken with a wide margin of safety. THE VERDE DISTRICT. The Verde district embraces the drainage basin of the Verde River and its tributaries, having a total area of 6,000 square miles, of which the greater part is in Yavapai County, only 700 square miles being in Maricopa County. In this district 1,948 acres of crops were irrigated successfully in the year ending June 30, 1890. The water supply in general is good, and a far larger area, now partly irrigated, can be watered. Among the principal tributaries of the Verde are Walnut, Granite, Oak, Beaver, and Clear Creeks. Walnut Creek is dry during a portion of the year, its waters being entirely diverted upon the adjacent land. 310 HYDROGRAPHY OF THE ARID REGIONS. On Granite Creek the supply is reported to be ample for the acreage under irrigation, but there is more land needing the waste waters of the floods. Oak Creek supplies an amount more than sufficient for the lands in the vicinity of Cornville. The other streams entering below carry larger quantities of water than is used at any time. The largest body of irrigated and easily irrigable lands is in the Verde Valley proper, which is situated in the southern part of Yavapai County, extending from a canyon 20 miles or more above Camp Verde to another narrow pass about 10 miles below the fort. In this valley large crops of alfalfa, barley, oats, wheat, corn, and potatoes are reported to be raised, as well as apples, pears, plums, peaches, and apricots. The Verde River here flows continuously, with an occasional flood from local rains. The water supply is good, but crops have suffered from acci- dents to canals or difficulty of turning the water into them. Measurements of the discharge of the Verde were attempted at a point about a mile above its junction with the Salt River, in order to obtain the amount discharged and its relative importance. The station at tliis point was operated in connection with one on the Salt River, about a mile above the Verde, and observations at both points were carried on during a large portion of the summer and fall of 1889. It was found impracticable, however, to obtain the daily heights on ac- count of the distance of these stations from the homes of persons who were competent to act as gauge observers, and the difficulty of measur- ing these rivers in time of flood necessitated the abandonment of the work in order to concentrate all efforts on the Gila River. The results of the measurements are given in the following table, and they may also be found in greater detail in the previous annual report. These do not show a very decided fluctuation of the river, but serve to give definite ideas as to the ordinary summer discharge of this stream: Verde River, 1 mile above Salt River. [Drainage area, 6,000 square miles.] Month. Discharge. Total for month. Run off'. Max. Min. Mean. Depth. Per sq.m. 1889. August 14 31 September Sec. -feet. 480 340 Sec. -feet. 154 140 Sec. -feet. 207 192 Acre feet. 12, 730 11,424 Inch. •04 •03 Sec. feet. •03 •03 THE UPPER SALT DISTRICT. The Upper Salt Basin lies between the Verde and the Upper Gila, and is similar in many respects to these headwater basins. The total area is G,2G0 square miles, of which 927 miles are in Yavapai County, 1,935 miles in Apache, 2,430 miles in Gila, 420 in Graham, 424 in Mari- copa, and 124 in Pinal County. Owing to the mountainous character of this district there were only 815 acres of crops cultivated by irrigation DAILY DISCHARGE OF THE SALT RIVER ABOVE PHENIX, ARIZONA. January. February. March. April. May. June. July. August. September. October. November. December. library OF THE UNIVERSITY Of ILLINOIS NEWELL.] HEADWATERS OF SALT RIVER. 311 in the census year. The valleys are in general narrow, the only open- ing of any importance being along the Salt River, between Pinal Creek and Tonto Creek. The water supply is, therefore, ample for all the ac- cessible land of this district. This basin may be taken as including the area of the Salt River head- waters down to the junction with the Verde. The country is rugged and heavily timbered at the higher elevations, and there are not many large valleys along the river where agriculture can be carried on. The principal streams entering from the north are Black River, Bonita, White Mountain, Carrizo, Cibicu, Canyon, Cherry, and Tonto Creeks, and from the south Pinal and Pinto Creeks. The principal agricultural land of the basin extends from a point below Pinal Creek to Tonto Creek, some farming being carried on also along Sally May Creek and Tonto Creek. Measurements of the water flowing out of this drainage basin were made, as stated above, at a point about a mile above the junction with the Verde, being carried on at the same time that measurements were made on that river, and later at a point in the canyons about 20 miles above the Verde. The results of these latter measurements are given in the following table, which exhibits the ordinary range in amount of the summer water: Salt River in canyon — 20 miles above the Verde. [Drainage area, 5,880 square miles.] Month. Discharge. Total for month. Run off. Max. Min. Mean. Depth. Sq. mile. 1890. Sec. feet. Sec. feet. Sec. feet. Acre feet. Inch. Sec. feet. May 28 31 520 520 520 31,980 •10 •09 Jmie 520 193 298 17, 731 •06 •05 July 375 185 215 13, 222 •04 04 August 1-28 2, 200 000 1.362 83. 763 ■27 •23 THE LOWER SALT DISTRICT. The Lower Salt district is the principal subdivision of the Gila Basin, since it includes the largest area of irrigated land and the greatest canal systems of Arizona. It may be said to begin at the junction of the Salt and Verde, and to extend to or below the great bend of the Gila, including on each side some of the most fertile land of the Terri- tory. The total acreage on which crops were raised by irrigation in the census year was 29,171 acres. This is but an insignificant portion of the total amount on which products might be raised with a sufficient water supply, for, as previously stated, there are enormous tracts of fertile land, whose extent is so great that no probable increase of water supply can cover them. The Salt River is the only source of water; the situation here is sim- ilar in many respects to that of the middle Gila district, but lias the advantage that the headwater districts do not contain such large 312 HYDROGRAPHY OF THE ARID REGIONS. bodies of irrigable laud as do the headwaters above the middle Gila. There is said to be ample water for the present acreage cultivated iu the fall and spring, but in summer the supply is scarce, so much so that crops have been lost, and trees and shrubs have perished for lack of water. In the Salt River Valley, in Maricopa County, the following canals were reported in 1889 as being taken from Salt River: Canals. Length. Canals. Length. Miles. 40 22 Miles. 6 5 14 22 18 4 9 4 19 3 Mesa 9 It may be added that, excepting in floods, all the water in Salt River has been utilized, and nothing more can be done in the way of land reclamation without the construction of storage reservoirs. If this were done it is estimated that sufficient water could be impounded during the storm floods to reclaim double the area now under cultiva- tion. The soil is very productive. Large crops of wheat, barley, and alfalfa are grown, and fruits of all descriptions flourish and yield bountifully. Measurements of the amount of water entering this subdivision were made, as before mentioned, by establishing stations on the Salt and Verde rivers, a short distance above their junctions, but these were continued only a few months as it was found impracticable with the small force available to keep up the work. Estimates of discharge, however, have been prepared by Mr. Samuel A. Davidson, engineer of the Arizona Canal Company. These are based upon weir calculations of the water flowing over the submerged dam built by this company at their headworks. These were begun in August, 1888, and daily obser- vations continued up to the present time, the results of which are kindly given by Mr. Davidson, as shown in the following table. Measurements of this character being based upon certain assumptions and the use of constants determined in a small way, their degree of accuracy is open to question, but, at least, these measurements, or rather the computa- tions based upon them, have a great value as showing the relative amounts of water in the different months and seasons. On PI. lxxix is shown graphically the daily mean discharge as com- puted by Mr. Davidson, and the irregular character and extraordinary fluctuations of the stream are clearly brought out. The most noticeable feature is the great flood of February 21, 1890, when, according to Mr. Davidson’s computations, the discharge increased suddenly from 1,000 second-feet to over 143,000 second-feet. This, however, is eclipsed DAILY DISCHARGE OF THE KAWEAH RIVER AT HOMER’S RANCH, CALIFORNIA, 1879 TO 1882. LIBRARY OF THE UNIVERSES °f Illinois NEWELL.] DISCHARGE OF SALT RIVER. 313 by the flood of February IS to 2d, 1891, which, is not shown upon FI. lxxix, the data being received too late for illustration. On Febru- ary 17 the mean discharge was 83d second-feet, increasing the next day to ld4,000 second-feet, and on the 19th to 276,000. This first flood diminished rapidly, averaging on the 20th only 69,100, and on the 22d 14,890. This was followed by a second swell greater than the first, the flood increasing until on the 24th a maximum of 300,000 second-feet was reached. This subsided almost as rapidly as it came, so that by the second day after the river was carrying less than Id, 000 second-feet. This flood was very destructive, carrying away bridges and portions of canals, submerging great areas in the Gila Y alley, and causing a sudden rise in the Colorado, as shown on FI. lxxiv, the greatest flood for that decade at least. The Arizona Canal Company’s weir across the Salt River was damaged, a portion of the canal washed out, and the channel of the stream so altered that computations of daily discharge could no longer be made without new data. Salt River, Arizona Dam, Arizona. [Drainage area, 12,260 square miles.] Month. Discharge. Total for month. Run off*. Max. Min. Mean. Depth. Per sq. mile. 1888. Sec. feet. Sec. feet. Sec. feet, Acre-feet. Inch. Sec. feet. 350 21, 525 . 03 . 028 350 20, 825 .03 . 028 October - 350 300 331 20; 356 .03 .027 November 5, 760 425 842 50, 099 .08 .068 December 43, 489 1,665 6,698 411, 927 .63 .545 1889. January 24, 953 1, 665 5, 947 365, 740 .56 .48 February 3, 940 1, 534 2, 605 144, 577 .22 .22 March 33, 794 3,563 8, 745 537,817 .82 .71 April 5, 559 2. 496 3,975 236, 512 .36 .32 May 1,784 622 1,039 63, 898 . 10 .08 June 615 356 470 27, 965 .04 .04 July 1,311 334 495 30, 522 .05 .04 August 755 389 417 25, 645 .04 .03 September 1, 172 389 521 31, 000 .05 .04 October 704 319 440 27, 060 .04 .04 November 629 532 576 34, 272 .05 .05 December 25. 371 557 5. 686 349, 689 .53 .46 1890. January 15, 750 1,376 4. 982 306, 393 .47 .40 February 143, 288 1,045 10. 097 560, 383 .86 .82 March 17,228 2, 566 6, 421 394, 891 .60 .52 April 2, 077 1.369 1. 840 109, 480 .17 . 15 May 1. 369 630 914 56,211 .09 .08 June 672 397 511 30, 404 .05 .04 July 872 397 524 32, 226 .05 .04 August 7, 734 1, 114 3, 885 238, 927 .37 .32 September 3,685 725 2, 339 139, 170 .21 . 19 ( Ictober 7,465 753 2, 768 160, 232 .25 .23 November 30, 504 766 4,717 280, 661 .43 .38 December 30, 366 1,110 6, 259 384, 928 .59 .51 1891. January 17, 127 L060 3, 416 210, 084 .32 .28 February 300. 000 825 39, 201 2. 175. 655 3. 32 3. 10 314 HYDROGRAPHY OF THE ARID REGIONS. THE LOWER GILA DISTRICT. The Lower Gila District may be said to include the arable land from Gila Bend to Yuma, where the Gila River empties into the Colorado. This is a main-trunk district, receiving the waters which escape from the Middle Gila District and from the Lower Salt, and since these in turn receive their waters from four head-water districts, it will be rec- ognized that the supply here depends very largely upon the action which is taken in these six subdivisions. There were only 555 acres on which crops were reported raised by irrigation in 1889, but a far greater acreage has been brought under ditch. There are a large number of extensive canals and ditch systems projected or under construction in this district, but whose success must apparently be a matter of some doubt. The land of the Lower Gila District is of great fertility and is adapted to the cultivation of many fruits of the semitropic zone, as, for example, oranges, lemons, and other citrus fruits. It is thus known as the cit- rus belt of Arizona, and promises to become of great importance in these productions. Besides the fruit, alfalfa, barley, and wheat are re- ported to be cultivated, and vineyards have been successfully planted. The following canals were reported as built or under construction in 1889, to take water from the Gila in Maricopa County: Canal. Length. Covers. Canal. Length. Covers. Miles. 30 Acres. 20, 000 5, 000 Miles. 14 Acres. 5, 000 2, 000 8 8 Enterprise 12 6^ 000 Gila River Irrigating Co 12 8 3, 000 12, 000 30 18, 000 Palmer 22 The Gila River Irrigating Company proposes to build a large dam at the Black Buttes below the mouth of the Hassayampa and carry water south and southwest, taking in the entire valley on both sides of the river to the Yuma County line, making a canal 75 miles long, covering 500,000 acres of land. The Gila Bend Company have completed 22 miles of their canal, under which 3,400 acres are reported to be irrigated at present. The names of the canals, together with their lengths and amount of land below each, taken from the Gila in Yuma County, as re- ported by the liydrographers, are given below : Canal. Length. Covers. Canal. Length. Covers. Miles. Acres. Miles. Acres. 35 40, 000 7 2, 000 5 1, 500 10 4,000 13 10, 000 8k 2, 000 22 12, 000 2, 500 10 i. ooo 3 LIBRARY OF THE UWVMSITrOF ILLINOIS U. 8. GEOLOGICAL SURVEY GAUGE HEIGHT OF THE KINGS RIVER A TWELFTH ANNUAL REPORT PL. LXXXII Jan. Feb. Mar. Apr. May. June. July. Aug. Sept. Oct. Nov. Dec. 12 feet. 9 feet. G feet. 3 feet. 12 feet. 9 feet. G feet. 3 feet. 12 feet. 9 feet. 6 feet. 3 feet. 12 feet. 9 feet. 6 feet. 3 feet. 12 feet. 9 feet. 6 feet. 3 feet. 12 feet. 9 feet. 6 feet. 3 feet. MGSBURG, CALIFORNIA, 1880 TO 1891. library OF THE UNIVFP^ NEWELL. ] LOST RIVER BASINS. 315 THE AGUA FRIA AND HASSAYAMPA DISTRICTS. The Agua Fria and Hassayampa districts lie south and west of the Verde Basin and between it and the Lower Gila District. The water supply of each is so small and the amount of arable land so large that they may each be considered as lost basins, although in time of large floods they may contribute to the Lower Gila. The total area of the Agua Fria Basin to Gilette is 1,420 square miles. The supply of water, however, is not sufficient for all crops under cultivation, and in very dry seasons some are lost. The head waters of this district are in Yavapai County, where the principal industry is grazing, while the great portion of the arable land is south of this, in Maricopa County. The Agua Fria rises in the mountains southeast of Prescott and Hows south as a clear mountain torrent, but as it enters the plains of the Gila the waters sink into the broad, sandy, channel. In flood times, however, a great volume of muddy water is poured through the usually dry channel, entering the Gila a short dis- tance below the mouth of the Salt River. The Hassayampa District lies to the west of the Agua Fria, and, like it, has its headwaters in Yavapai County. Of the total area of 1,810 square miles in this district, about 937 square miles are in this county and 873 square miles in Maricopa County. In the headwaters of this basin was the Walnut Grove Dam, whose destruction in February, 1890, was the cause of considerable loss of life and property. On PI. lxxvii is given a view of the reservoir formed by this dam. Hassa- yampa Creek, like the Agua Fria, is subject to violent freshets, whose waters reach the Gila, but at other times the stream sinks into the sands. THE SANTA CRUZ DISTRICT. The Santa Cruz District lies in the southern portion of the Gila Ba- sin west of the San Pedro District. The limits of this district are ex- tremely difficult to define, on account of the lack of good maps of the region. There are, however, approximately 3,500 square miles in this district, of which a small part of the head waters is in the Republic of Mexico and the remainder in the county of Pima, Arizona. The principal streams of this district are the Santa Cruz River and its tributaries, the Sonoita and Potrero. These creeks rise in the moun- tains of the south, where the elevation is from 4,000 to 5,000 feet, and join to flow northward as the Santa Cruz. The waters are finally lost in the sands not far from Tucson. In the upper part of the stream, among the rocky canyons and narrow valleys, is ample water, but in the lower portion of the stream there is, during the dry season, an amount insufficient to supply all the needs of the present acreage under cultivation, of which in all there was, in 1889, 2,G72 acres. In addition to the lost river basins before mentioned there are in the great drainage basin of the Gila areas aggregating 33,300 square miles, over which the rainfall either does not give rise to streams, or if little 316 HYDROGRAPHY OF THE ARID REGIONS. streams are formed, they do not attain notable importance. Scattered through this region, much of it fertile land, are small localities where water can be brought from springs or pumped from saturated beds below the surface to irrigate small farms or gardens of stock-raisers. On the plains are many places where there is grass enough for herds of cattle if only water can be obtained sufficient for their needs. Deep wells have been sunk for this purpose, and large tanks for holding storm waters constructed, and occasionally there is obtained a surplus of water, by which a few plants are sustained. Tins method of irrigating will unquestionably spread gradually, but there is little to require the attention of others than those locally interested. The problems here are such that each man must solve his own for himself, and thus are in sharp distinction from the condition of affairs in the great districts above described, where the action of every man in his use of water has its influence, though slight, upon the prosperity of others. SACRAMENTO AND SAN JOAQUIN BASINS. In these basins, lying wholly within the State of California, a careful examination of the water supply was begun in 1878 by the engineering department of that State, under the direction of its engineer, Mr. William Hammond Hall. Hydrographic measurements of an extensive char- acter were begun and carried on successfully through several years, and a large amount of information bearing not only upon irrigation, but also upon the improvement of rivers, the flow of mining detritus, and drainage of swamp lands. At that time gauging stations were established, these being in many instances at or near railroad bridges crossing the streams, the height of the water being kept by employes of the railroad. Many of the gauges established at that time have been kept in good order and read at regular intervals up to the present time. Credit is due to the officials, especially the chief engineer, of the Southern Pacific Company for the continuation of these gauge-height readings, whose value in connection with discussions of river flow is of the highest order. In 1889 Mr. Hall, then supervising engineer for this Survey, began a series of measurements on certain rivers on which gauging stations had previously been established by the California State engineering de- partment and the fluctuations of whose waters had been recorded by the railroad employes. The results, however, of these last attempts lie chiefly in the perfection of the methods to be employed on such streams and the devising of an apparatus for gauging from the shore, as described in the preceding annual report. Briefly stated, the results of the river-gauging work of the State engineering department of California are as follows. The field work began in June, 1878, and during part of that and the succeeding year several parties were engaged in making gaugings of rivers and canals in connection with careful surveys for the purpose of acquiring facts library OF THE UNIVERSITY OF ILLINOIS January. February. March. April. May. June. July. August. September. October. November. December. 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 U. S. GEOLOGICAL SURVEY O o lO 3 o 8 8 as CO TWELFTH ANNUAL REPORT PL. LXXXIII DAILY DISCHARGE OF THE SAN JOAQUIN RIVER AT HERNDON, CALIFORNIA, 1879 TO 1882. LIBRARY OF THE UNIVERSITY OF ILLINOIS NEWELL.] CALIFORNIA GAUGINGS. 317 bearing upon the solution of the problems of drainage, river improve- ment, mining detritus, and irrigation. Gauging surveys were made of the Sacramento at five places, viz, at Colusa, at Butte Slough, at Knight’s Landing, at the mouth of the Feather Kiver, and at the mouth of the American River, and also a survey of the American River itself. At the same time a second party made gaugings of Kings, San Joaquin, Fresno, Chowcliilla, Mariposa, Merced, Kaweah, and Tule Rivers. A third party examined the San Joaquin from the Stanislaus north, and a fourth party made gaugings up toward the headwaters of the Sacramento, namely on the Cosumnes, American, Bear, Yuba, Feather, and intermediate streams, as well as on the creeks northward to Chico Creek; also the Sacramento, both at Tehama and in the Iron Canyon, above Red Bluffs, and Stony Creek, besides all the other tribu- taries north of Stony and Chico Creeks. Observations of river height were maintained for a time on all the principal streams. There were in all, during the years 1878 and 1879, ninety-one gaugings made on rivers and two hundred and forty-three on canals, and there were es- tablished six self- registering tide gauges, one hundred and twenty-seven height rods or udometers on rivers and fifty-two on canals. The gaugings on large rivers were made mainly by current meters, but on the small streams and canals the discharge was computed by means of float observations or in some instances by Kutter’s formulae. In some cases careful surveys were made at each guaging station extend- ing for several miles, with cross sections every 100 feet, or with less care for 1 or 2 miles with cross sections at less intervals, down to a distance of one-half mile and sections every 200 feet. On the creeks and canals the general length of gauging survey was from 600 to 1,200 feet. All the rods and height gauges were connected by leveling, giving their rela- tive elevation and the slope of the river from place to place. In 1880 field work was continued, the gauging stations in the San Joaquin were put in repair and records collected; regaugings were also made of the Kern River and of the canals. In Los Angeles County in the summer thirty streams and ditches were gauged, and later in the season the discharge of eighty-eight small streams, ditches, artesian wells, etc., were obtained by making one hundred and eighty-three gaugings. At about the same time the low-water discharge of the streams flowing into the San Bernardino Valley was estimated by means of twenty-three guagings. This practically ended the field operations of the State engineering department as far as hydrographic work was concerned. From the data obtained in the field computations of discharge were made for most of the rivers mentioned above, and the results of the gaugings and computations were published in 1886 in a volume entitled “Physical Data and Statistics of California,” in which are given for each month and season, from November, 1878, to October, 1885, the maximum, minimum, mean, and total discharge in second-feet, together 318 HYDROGRAPHY OF THE ARID REGIONS. with, in most cases, the depth of water drained and the amount drained per square mile from the basins of the following- rivers, viz : Sacramento River, at Collinsville. Cosunmes River, at Live Oak Suspension Bridge. Dry Creek, at base of foothills. Mokelumne River, at Lone Star Mill (base of foothills). Calaveras River, at Bellota. Stanislaus River, at Oakdale. Tuolumne River, at Modesto. Merced River, at Merced Falls. Bear Creek, at base of foothills. Mariposa Creek, at base of foothills. Chowcliilla Creek, at base of foothills. Fresno Creek, at base of foothills. San Joaquin River, at Hampton ville. Kings River, at Slate Point (base of foothills). Kaweah River, at Wachumna Hill. Tule Kiver, at Porterville. Deer Creek, at base of foothills. White Creek, at base of foothills. Poso Creek, at base of foothills. Kern River, at Rio Bravo Ranch. Oaliente Creek, at base of foothills. The information obtained from the State engineering department of California and from the Southern Pacific Company relating to the gauge height and discharge of the rivers in this basin is presented herewith on Pis. lxxx to lxxxviii, in order to afford an opportunity of compar- ing the behavior of these streams with those in other parts of the arid region. These plates are arranged in geographic order, following the rule elsewhere laid down of taking the tributary streams in succession from the headwaters to the mouth. The headwaters of the San Joa- quin, being nearest the Colorado Basin, are first presented. In the cases of many important streams, the height of whose waters has been recorded for a series of years, the relation between the dis- charge and height has not as yet been obtained. Although our knowledge would be far more complete if the daily discharge were known, yet the range of height of the river for a long period gives many facts of importance and is of sufficient value to justify the representation of these fluctuations. The curve of average height for all the years during which gauge readings were made is placed on these diagrams. This may be considered the normal curve for the river, and when placed in connection with the actual fluctuations of the stream each year, the abnormal variations of that year are at once apparent. In looking over these plates it will be seen, for example, that on some years the height remains persistently below the normal, while on others it is above, and still on others varies widely in both directions. As a matter of course no year follows exactly the normal or average curve. library OF THE UNIVERSITY' OK ILLINOIS U. S. GEOLOGICAL SURVEY GAUGE HEIGHT OF THE SAN JOAQUIN RIV TWELFTH ANNUAL REPORT PL. LXXXIV 12 feet. 9 feet. 6 feet. 3 feet. 12 feet. 9 feet. 6 feet. 3 feet. 12 feet. 9 feet. G feet. 3 feet. 12 feet. 9 feet. 6 feet. 3 feet. 12 feet. 9 feet. 6 feet. 3 feet. 12 feet. 9 feet. G feet. 3 feet. HERNDON, CALIFORNIA, 1880 TO 1891. LIBRARY OF THE UNIVERSITY OF ILLINOIS NEWELL.] UPPER TRIBUTARIES OF SAN JOAQUIN. 319 KERN RIVER. Kern River is the largest stream in the southern end of the San Joa- quin Valley, draining a large area in the mountains west of the main range of the Sierra Nevada. This stream has been gauged at the Rio Bravo Ranch, just below the point where the river leaves the canyons and above the irrigating canals, this locality being about 12 miles from Bakersfield. The record of river heights was kept for 1879, 1880, 1881, and 1882, and daily mean discharges, shown graphically on PI. lxxx, were computed for these years. By referring to this plate the wide range in annual discharge is seen, and also the characteristic irregular fluctuations. In 1879 there was apparently no spring flood, but in place of this almost continuous low water, broken only by slight fluctuation, as rep- resented on the diagram by the dotted line. In 1880, on the other hand, the discharge, shown by the flue black line, reached the maximum ot 4,070 second-feet in June, and the flood as a whole was large and per- sistent, being preceded by a sharp rise on April 3 and extending to the end of July. The high water of 1880 continues into 1881, as shown by the line consisting of dots and dashes. This flood, however, did not reach the height of that of the previous year, but attained its maximum early in May, and then with minor fluctuations fell rapidly through June and July. In 1882 the discharge, as indicated by the heavy black line, was in- termediate between those of previous years, coinciding in winter and late summer fairly well with the discharges of 1879 and 1880. In addi- tion to these, the mean discharges for 1883 and 1884 have been pub- lished in the Physical Data and Statistics of California, having been computed by using the rainfall measurements of these years as a basis and assuming a certain relation between these and the river flow. TULE RIVER. The drainage area of tliis river lies west of the head waters of the Kern, the main stream flowing directly westward and emptying in time of floods into Tulare Lake. At other times the water is all used for Fig. 227.— Diagram of daily gauge height of the Tule River, California. purposes of irrigation from Porterville to Tipton. Measurements were made about 5 miles above Porterville, but below the head of the Pioneer Canal. The gauge height only for this stream is shown on Fig. 227, for 320 HYDROGRAPHY OF THE ARID REGIONS. the greater part of 1879 and the spring of 1880. This fragmentary record serves to give in a general way the character of the stream during those years. In the early part of 1879 the water, as in the case of the Kern River, was extremely low, and the flood rise is scarcely apparent. At the beginning of the succeeding winter, however, the water began to rise and continued until April, when there was a slight fall, succeeded in the latter part of May by a sudden flood, the effect of this flood being felt far into the summer. The mean monthly discharge of this river for these and the succeeding years up to and including 1884 has been published, 1 and also the mean discharges for the same period of the adjoining creeks, the Deer, White, and Poso. KAWEAH RIVER. The Kaweah drainage area lies between that of Tule River and of Kings River. The river enters the San Joaquin Valley northeast of Tulare Lake and furnishes water for large areas in the vicinity of Visalia. Discharge measurments were made principally in the vicinity of Three Rivers, being thus in the mountains above some of the smaller tributaries. The discharges for 1879, parts of 1880, 1881, and 1882 are shown on PI. lxxxi. The discharge for 1879, as in the case of the rivers above mentioned, was very small, but in 1880 heavy floods occurred, some of which, as for example that of April 20, were of unusual violence. The record from July 1, 1880, to June 30, 1881, has not been preserved, but the fall and winter of 1881 are shown and the spring of 1882, the discharge for this latter period being indicated by a heavy black line. KINGS RIVER. The State engineers found this important river exceedingly difficult to measure, on account of the shifting character of its bed and banks or of other obstacles. Gaugings, however, were made by them at various points, by means of which they were enabled to make computations of the discharges from 1879 to 1884, inclusive. One of the most important factors in this computation was the record of gauge height kept at the Southern Pacific Company’s bridge near Kingsburg. This record, which has been maintained up to the present time, is given on PI. lxxxii, in connection with the curve of average river height for the entire period. This diagram exhibits the relative height of tbe river in each year and the time of occurrence and extent of the floods, as, for instance, in the years 1880 and 1881 the water in general was above the average, while in 1882 and 1883 the spring floods did not reach their usual height. In 1884 the flood was large, and especially notable from the fact that 1 Physical data and statistics of California, collected and compiled by the State engineering depart- ment of California, William Ham. Hall, State engineer, Sacramento, State printing office, 1886, pp, 459 460 . DAILY DISCHARGE OF THE MERCED RIVER AT CENTRAL PACIFIC RAILROAD BRIDGE, CALIFORNIA, 1879 TO 1882. January. February. March. April. May. June. July. August. September. October. November. December. library OF THE UNIVERSITY Of ILLINOIS NEWELL.] GAUGINGS OF SAN JOAQUIN. 321 it occurred late in the season, a great part coining in July. During the year following the water remained low, and in 1886 was a trifle above the normal. The years 1887, 1888, and 1889 were similar in character as regards the small size of the floods, while 1890 rivaled 1884 for the extent of high water. SAN JOAQUIN RIVER. The San Joaquin was gauged both at the edge of the valley and at the Southern Pacific Railroad crossing, near Sycamore, now Herndon, the record at this lower point, however, being the most extended, hav- ing been kept by the Southern Pacific Company continuously to the present year. The discharge for this place for the years 1879, 1880, 1881, and 1882 is shown on PI. lxxxiii. On account of the peculiar irregular character of these discharges, they are represented in two groups, 1879 and 1880 being placed together, and also 1881 and 1882 by themselves, since the lines for these last two years would fall inter- mediate between those for the preceding two years. Low water for 1879 and high floods in 1880 are shown to have characterized this river as well as those farther south. The sudden flood of February 1, 1881, almost equaling those of May and June of the preceding year, is notable as showing the irregularity in time of these freshets. It is interesting to compare these lines with those repre- sen ting the discharges of rivers in Colorado, Utah, and Montana, where the floods are more gradual and do not as a rule occur with such vio- lence. It is to be noted that these sharp irregular fluctuations are due to changes of temperature' rather than to rainfall, most of the floods being caused by the melting of the snow among the mountain summits, the effect of the flood being of course intensified by warm rains, if these occur. The mean monthly discharge for these years and for 1883 and 1884 lias been computed by the California engineers, and could probably be estimated up to the present time from the gauge readings kept at Herndon. The gauge heights themselves are, however, given on PI. lxxxiv for direct comparison among themselves. The heavy flood of 1880 is apparent by the position of the black line above the dotted, and the smaller floods of 1881 and 1882 can also be seen. In 1884 the flood was the greatest recorded both in amount and duration, as was the case in the Colorado basin, as previously noted. The year 1885 was noted by the continuance of the river height for long periods below the normal, and 1886 by an equal persistency above the normal. In 1887, 1888, and 1889 the river continued at low stages, but in 1890 rose again to heights unknown since 1884, falling off in the winter, the beginning of 1891 being marked by unusually low water. By comparing diagrams of discharge for 1880, 1881, and 1882 with those of gauge height for the same period, the difference between these two classes of graphic illustrations is apparent. As the water rises a 12 geol., pt. 2 21 322 HYDROGRAPHY OF THE ARID REGIONS. 16 ft. 14 ft. 12 ft. 10 ft. 8 ft. 6 ft. 4 ft. 2 ft. 16 ft. 14 ft. 12 ft. 10 ft. 8 ft. 6 ft. 4 ft. 2 ft. greater and greater amount flows in tlie stream for every increase in height. The diagram of discharge is so drawn that the vertical spaces represent equal quantities of water, while in the gauge height diagrams the vertical distances represent heights of water without regard to quantity. Thus the two diagrams show the same fluctuations on the same days. The lower parts of both diagrams are very nearly alike, since at low stages the discharge increases very nearly with the addi- tional height, but the upper part of the discharge diagram in compari- son with that of gauge height appears as though stretched out in a vertical direction, from the fact that the quantity discharged at the high stages is increasing rapidly. MERCED RIVER. The discharges for this river at the gauging station near the railroad bridge between Delhi and Livingston are given on PI. lxxxv for the years 1879, 1880, 1881, and 1882. As shown by the diagram, these dis- charges show great irregularities, but during May fall within a com- paratively small range. The early floods of the year are particularly noticeable for their intensity, as, for instance, that of 1881. TUOLUMNE RIVER. The Tuolumne is one of the most important rivers in the northern part of the San Joaquin Valley. It flows nearly due west from the 16 ft. 14 ft. 12 ft. 10 ft. 8 ft. 6 ft. 4 ft. 2 ft. 16 ft. 14 ft. 12 ft. 10 ft. 8 ft. 6 ft. 4 ft. 2 ft. Sierra Nevada, the waters being used for irrigation in the viciuity of Modesto. The gaugiugs of this river were made near the railroad bridge Fig. 228.— Diagram of the daily gauge height of the Tuolumne River, California, 1890 and 1891. LIBRARY OF THE UNIVERSITY OF ILLINOIS January. February. March. April. May. June. July. August. September. October. November. December. 5 10 15 20 25 5 10 15 30 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 U. S. GEOLOGICAL SURVEY TWELFTH ANNUAL REPORT PL. LXXXVI DAILY DISCHARGE OF THE TUOLUMNE RIVER AT MODESTO, CALIFORNIA, 1879 TO 1882. January. February. March. April. May. June. July. August. September. October. November. December. 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 U. S. GEOLOGICAL SURVEY TWELFTH ANNUAL REPORT PL. LXXXVII § © © O O © O I § 8 8 8 1 DAILY DISCHARGE OF THE MOKELUMNE RIVER AT MAGEE’S MILL, CALIFORNIA. 1879 TO 1882. 12 feet. 9 feet. 6 feet. 3 feet. 12 feet. 9 feet. G feet. 3 feet. 12 feet. 9 feet. G feet. 3 feet. 12 feet. 9 feet. 6 feet. 3 feet 12 feet 9 feet. G feet. 3 feet. 12 feet. 9 feet. 6 feet 3 feet U. S. GEOLOGICAL SURVEY GAUGE HEIGHT OF THE LOWER SAN JOAQUIN RIVER AT ( feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. ?AL PACIFIC RAILROAD BRIDGE, CALIFORNIA, 1880 TO 1891 of NEWELL.] LOWER SAN JOAQUIN DRAINAGE. 323 south of the town, the record being kept for many years by the railroad company. The discharges are shown on PI. lxxxvi, those for 1879 and 1880 on the upper half of the page, and for 1881 and 1882 on the lower half. The discharges of these years show the characteristic fluctuations, 1879 being low, 1880 high, and 1881 and 1882 in general intermediate. The daily gauge height of this river for 1890, and a part of 1891, is shown on Fig. 228, the discharges not having been computed. This serves, however, to show the relative fluctuations during the various months of these years and the irregularity iu the character of the stream. MOKELUMNE RIVER. The Mokelumne River enters the Sacramento Valley at about one- tliird of the distance from Stockton to Sacramento. It is considered a tributary of the Sau Joaquin, for although flowing toward the Sac- ramento, when within about 2 miles of that river its waters turn abruptly toward the south. The flow was measured on the edge of the valley above Clements, giving the discharges shown on PI. lxxxvii. In this case, as in that of previous rivers, 1879 and 1880 are shown to- gether on the upper half of the page, and 1881 and 1882 on the lower half. The difference in discharge between 1879 and 1880 is not as strongly marked as in the case of the rivers farther south, and when the discharges for the four years are plotted on the same sheet the re- sult is a confused mass iu which no one year is particularly prominent for the quantity of its discharge. The excessive floods of early spring, as in 1879 and particularly in 1881, are the most noticeable features of these diagrams. The rapid fluctuations in quantity, so characteristic of the streams of this basin, are exhibited on this river. The culmination of the floods in the latter part of May and their gradual decline in June is clearly shown. LOWER SAN JOAQUIN RIVER. The height of the San Joaquin has been observed for a number of years by the Southern Pacific Company at its bridge. These daily gauge heights have been plotted, and are shown in condensed form on PI. lxxxviii, giving the fluctuations in height from 1880 to the present time. The average height of the river for each day in the year during the series of years through which observations were made is indicated by the dotted line, the irregular line showing the daily variations in each year from this average. In examining these in detail it will be seen that the flood of 1884 is, as in other cases, far above the normal. In the diagram for 1886, at the top of the plate the discharges for floods in January and May, are so great as to bring the line above the upper margin of the plate. The amount by which this line overruns is shown by the dotted lines immediately below these places. In 1887, 1888, and 1889, the height is in general below the average, but in the fall of the latter year the water rose suddenly and continued at an un- 324 HYDROGRAPHY OF THE ARID REGIONS. precedented height during that winter, the volume during each month almost equaling that of the Hood discharge of May or June. This great flood continued through July, and then declined, reaching the normal at the end of the year, the beginning of 1891 being marked by low water. THE GREAT BASIN. This term is applied to that vast extent of country lying between the Rocky Mountains and the Sierra Nevada, and embracing an area of 228,150 square miles, from which no water escapes to the ocean. The rain which falls within this area collects in the streams, and these in turn unite, forming large rivers in certain parts of the basin ; but in spite of their size they are destined sooner or later to disappear, either by evaporation from their broad sandy channels or from the surface of some saline lake. The larger rivers are on the extreme eastern or west- ern sides of this basin, for it is here only that lofty and continuous ranges of mountains are found. On the north the divide between the drainage of the Columbia is not sharply defined by great mountains, nor is it on the south adjoining the Colorado. Stream measurements have been made by the Geological Survey on the principal streams on both sides of the Great Basin. On the west- ern edge the Truckee, the principal river of the Pyramid Lake drainage basin, lias been measured in several places, and also the Carson, whose waters disappear in Carson Sink. On the eastern edge of the Great Basin, in the Salt Lake Basin, measurements have been of the principal streams, the Bear, Weber, Provo, and others, and in the Sevier Basin of the Sevier River mainly at the point where it enters the Sevier Desert. The results of these measurements are given in the following pages in the order stated. The gauging stations have been described in the preceding annual report of this Survey. In the case of the Bear and Sevier rivers a somewhat detailed description of the topography is given, in so far as it relates to the questions of water supply and irri- gation. ’ TRUCKEE RIVER. On PI. lxxxix is shown the discharge for the greater part of 1890 of Prosser Creek, the Little Truckee, and the Truckee below Boca, Cali- fornia. Prosser Creek and the Little Truckee flow into the Truckee a short distance above this town, and consequently the discharge below Boca includes that of these two streams. As might be expected, these discharges follow each other closely, since, the drainage basins being small, similar climatic conditions prevail over all. Measurements were made of the Truckee at two points farther down the river — one at Laughtons, about *3 s > . c , cji = o Ut o 8 2 TWELFTH ANNUAL REPORT PL- C NEWELL.] LOWER SEVIER RIVER. 343 cutting its way first through a great accumulation of gravels, the delta of the ancient river. At this point two canals have been taken out to supply the town of Leamington and the agricultural district below. About 40 miles farther down is the Deseret Reservoir. At this point the inhabitants of the towns of Deseret and Oasis have cut a channel for the river 400 feet long, shortening the course about a mile, so that the river, instead of pursuing a tortuous channel around a large loop, now pours through this cut-off across what was previously a narrow neck of laud. The loop thus abandoned has been blocked tip at both ends by earth dams and is now used as a reservoir, receiving its water by a long canal which runs up the river until it reaches a point suffi- ciently low for the water to be diverted into it. There is at present constructed, running from this reservoir, a canal which passes out through a cut 22 feet deep and 24 feet wide on the bottom, which leads to the town of Deseret. A new canal is projected to take water from the middle of the old reservoir and irrigate other lands for the purpose of starting a new colony. The local engineers have estimated that, by raising the earth dams and building better reg- ulating gates, sufficient water can be held in times of floods to supply the needs of this new community. This reservoir will be an example of storage at low elevations near the land to be irrigated. The situation is such that it is almost impos- sible to provide a better system for these towns. The Sevier winds through so many long, fertile valleys in its course, the water being taken out by innumerable canals, that it is impossible for the irrigators living out on the desert to provide storage for themselves in the high moun- tains, for the question of the distribution of water which has flowed through five or six counties would involve interminable conflicts. Their only resource, therefore, is to attempt to hold some of the flood and seepage water which has come from the irrigated lands a hundred miles or more above. From the above description of the river and the towns and communi- ties depending on its waters for sustenance it will be seen that the most careful study must be made of all the conditions before a general sys- tem of storage can be inaugurated which will be beneficial to all. There is no doubt that reservoirs in the mountains at the headwaters will be of great value and advantage even to the people who live down in the Sevier desert, as by their presence in the mountains the summer flow of ground water must be increased. On the other hand, to directly benefit the lower towns it will be necessary to construct at points in the lower end of several of the populated valleys reservoirs which will hold at these points the local flood waters, and deliver them to the agricul- tural lands in the next valley below. But before any such system of storage can be successfully carried into effect a general understanding will be necessary among the towns and counties interested, by which the whole body of irrigators shall 344 HYDROGRAPHY OF THE ARID REGIONS. join in tlie system of water storage and then distribute the waters thus saved according to the judgment of all interested. The discharge of this river at the Leamington gauging station from August, 1889, to June, 1891, is shown on PI. c., the less discharge of this latter period being very noticeable. The amount of water passing this station is of course greatly affected by the large diversions of water all along the river, and in years of scarcity, as in 1891, the flood dis- charge must come mainly from the lower tributaries, that from the higher forks of the stream being used in the many large canals. SNAKE RIVER DRAINAGE. Stream measurements have been made of the principal tributaries of the Snake River in eastern Idaho, and also of lower tributaries in west- ern Idaho and Oregon. A brief description of the topography of the country and of the gauging stations was given in the preceding annual report. The discharges at these stations are shown on Pis. ci to cvi. The discharges for Henry Fork, Falls River, and Teton, as well as for the Snake at Eagle Rock or Idaho Falls, are similar in general char- acter, differing mainly in the quantity of water represented, but the diagrams for the Owyhee, Malheur, and Weiser exhibit distinctive char- acteristics, only to be explained by a careful study of the topography of the region. The diminished floods of 1891 are very noticeable, and these are not only less in quantity, but culminate at an earlier date. The diagram for the Weiser is peculiar for the number and extent of the fluctuations of high and low water and the irregularity of the time at which these occur. DAILY DISCHARGE OF THE HENRY FORK ABOVE FALLS RIVER, IDAHO. DAILY DISCHARGE OF FALLS AND TETON RIVERS ABOVE CANALS, IDAHO. January. February. March. April. May. June. July. August. September. October. November. December. 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 DAILY DISCHARGE OF THE SNAKE RIVER AT IDAHO FALLS, IDAHO. January. February. March. April. May. June. July. August. September. October. November. December. 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 DAILY DISCHARGE OF THE OWYHEE RIVER AT RIGSBY, OREGON. ^ Or Ci SI po iO January. February. March. April. May. June. July. August. September. October. November. December. 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 5 10 15 20 2 ; DAILY DISCHARGE OF THE MALHEUR RIVER AT VALE, OREGON. January. February. March. April. May. June. July. August. September. October. November. December. DAILY DISCHARGE OF THE WEISER RIVER ABOVE WEISER. IDAHO. TWELFTH ANNUAL REPORT PL. CVI DISCHARGE TABLED The following tables give the monthly discharges for the rivers upon which observations of height have been made during the year ending June 30, 1801. These tables are similar in form to those published in the preceding annual report of this Survey, 1 being in fact continuations of many of them. At the head of each table is the name of the river and also the locality at which the measurements were made, together with the total drainage area in square miles above this point. The first column gives the mouth, and in cases where observations were made during a portion of the month, the dates during which these were continued are shown immediately after the name of the month. In such cases the mean discharge is not that of the whole month, but of this fraction only. Under the head of “discharge” are given the maximum, minimum, and mean discharges for each month or portion of month in cubic feet per second. In several instances to complete a year estimates have been made of the mean discharge, these estimates being marked by an asterisk. At the right of the mean discharge in second-feet are the total dis- charges for the entire month in acre- feet; that is, the number of acres that would be covered to a depth of 1 foot by a stream of this given size flowing coutinuously through the month, none of the water being lost. The last two columns on the page show the relation existing be- tween this quantity of water and the area from which it may be sup- posed to have come. For purposes of comparison it is assumed that this water came in equal quantities from each square mile or acre of the drainage basin, although as a matter of fact this is recognized as im- possible, since in nearly all cases the water running off a large drain- age basin comes from comparatively restricted localities. The first of these two columns gives the depth of run-off for each month in inches ; that is to say, this quantity of water would, if put upon a plain of equal area, cover it to the depth given. The last column gives the run-off in second-feet for each square mile of the basin ; or, in other words, each square mile, taking the average for the entire area drained, contributed a constant supply of the given number of second- feet. 1 Eleventh Annual Report of the U. S. Geological Survey, Part ir, Irrigation, pp. 93-106. 345 346 HYDROGRAPHY OF THE ARID REGIONS, IFest Gallatin River, near Bozeman, Montana. [Drainage area, 850 square miles.] Month. Discharge. Total for month. Kun-off. Max. Min. Mean. Depth . Per sq.m. 1889. Secondft. Secondft. Secondft . Acre ft. Inches, Secondft. August 16 to 31 437 402 426 26, 200 0-58 050 September 640 402 450 24, 550 •54 •53 October 437 367 402 24, 700 •54 •47 *400 23, 800 *52 •47 *400 24, 600 •54 •47 1890. *320 19 680 *43 •38 *320 17 760 •39 •38 March 23 to 31 320 320 320 19, 680 •43 •38 April 1,255 280 460 27, 400 •60 •54 May 3, 195 1,300 2,092 128, 600 2-84 2-46 June 3, 800 2,060 2,641 157. 300 347 311 July 2, 165 890 1,388 85, 362 1-88 1-63 August 890 570 761 46, 800 1-03 •89 September 690 570 607 36, 100 •80 •72 October 650 570 591 36, 400 •80 •70 November 570 430 506 30, 100 ■66 •60 *450 27, 650 •61 •54 1891. 400 24, 600 •54 *47 400 22, 200 •47 •47 450 27 675 •61 •53 500 29, 750 •65 •59 May 2,535 1,390 1,897 116, 665 2-57 2'23 June 2, 975 1,615 2, 516 149, 702 3-30 2-95 Estimate. Madison River at Red Bluff, Montana. [Drainage area, 2,085 square miles.] 1890. Secondft. Secondft. Secondft. Acreft. Inches. Secondft. *1, 200 73, 800 0*66 0-58 *1,200 66, 600 •60 *58 *1, 200 73,’ 800 •66 •58 April 4 to 30 2, 580 1,370 1620 96| 390 •87 •78 May 6, 420 3, 060 4, 823 296, 600 2-67 2-32 June 6, 360 3, 780 4, 977 296, 131 2-66 238 July 3,660 1,715 2, 518 154, 800 1-39 1-21 August 1, 640 1,375 1,535 94, 400 •85 -74 September 1,580 1,420 1,466 86, 300 •78 •70 October 1,520 1,420 1,498 92, 300 •83 •72 November 1,470 1,285 1,380 82, 150 •74 •66 December 1, 520 1,285 1, 400 86, 150 •77 •67 1891. J anuary 1,580 1,240 1,406 86, 469 •78 •67 February 1,580 1,265 1,436 79, 698 •72 •69 March 1, 790 1,470 1,631 100, 306 •90 •78 April 1,960 1, 640 1,774 105, 530 •95 •85 May 4,260 1,790 3, 389 208, 423 1-88 162 June 4, 620 3,780 4, 167 247, 936 2-20 200 Estimate. NEWELL.] RIVER DISCHARGES BY MONTHS. 347 Month. 1890. January February March April 17 to 30 May June July A ugust September October November December 1891. January February March April May June 1889. August 5 to 31 September October November December 1890. January February March April May June J uly August September October November December Missouri River at Craig, Montana. [Drainage area, 17,615 square miles.] Discharge. Total for Run-off. Max. Min. Mean. month. Depth. Persq.m. Second-ft. Second-ft. Second-ft. Acre-ft. Inches. Second-ft. *3, 000 184, 500 •20 •17 *3, 000 166, 500 T8 *17 *3, 000 184, 500 •20 *17 6, 100 3,595 4, 662 277, 389 •29 •26 12, 500 6, 900 10, 472 644, 030 •68 •59 11, 900 8, 100 10, 074 599, 401 •64 ■57 7,800 2,614 5, 020 308, 730 •33 •28 2, 505 . 1,960 2, 216 136, 284 T5 T3 2, 396 1,960 2, 232 132, 700 T4 •13 2, 722 1, 742 2, 379 146, 000 T6 T3 3,159 2, 723 2, 868 170, 800 T8 TO 3, 159 1,742 2, 763 170, 000 T8 •16 3, 823 1,742 2, 967 184, 270 T9 T7 *3, 500 215, 250 •24 •20 *4, 000 246, 000 •26 •23 9, 130 4, 570 5, 794 344, 743 •37 •32 12, 050 7, 150 9,015 554, 422 •59 •51 16, 355 11, 000 13, 645 811,877 •85 •77 * Estimate. Sun River above Augusta, Montana. [Drainage area, 1,175 square miles.] 221 200 213 13, 100 •21 •18 260 200 214 12, 720 •20 •18 200 200 200 12, 300 •20 •17 200 180 191 11, 360 •18 •16 *175 10, 760 •17 •15 *175 10, 760 •17 *15 *175 9, 712 •15 •15 *175 10! 760 *17 *15 1,580 160 371 22, 050 •35 •31 4, 085 1,990 2, 804 172, 500 2-75 2-38 4, 000 1, 850 2, 342 139, 500 2-23 1-99 2, 440 450 961 59, 100 ■94 •81 480 315 371 22, 800 •36 T9 365 260 304 18, 090 •29 •26 480 240 315 19, 395 •31 •27 390 275 322 19, 160 •31 •28 340 240 267 16, 430 •26 •23 * Estimate. Y ellowstone River at Horr, Montana. [Drainage area, 2,700 square miles.] 1889. August 12 to 31 1,853 1,411 1, 660 102, 090 •71 •62 September 1,653 1, 126 1,270 75, 570 •52 •47 October 1, 126 841 976 60, 000 •42 •36 November 841 651 743 44, 200 •31 •27 *G50 39, 975 •28 *24 1890. *550 33, 825 •23 •25 *550 30, 525 •21 •25 March 21 to 31 620 560 585 35, 977 •25 •22 April 4, 495 510 1, 417 84, 250 •59 •53 May 11,915 5, 090 7, 522 466, 500 3-24 2-79 June 11,915 8, 720 10, 082 603, 000 419 3’74 J uly 9,410 5, 760 7, 682 473, 000 3-28 2-84 August 5, 600 3, 145 4, 375 269, 000 1-87 1-62 September 3,145 1,670 2, 276 135, 200 •94 •84 October 1,920 1 160 1,473 90, 600 •63 •55 November 1, 160 850 970 57, 750 •40 •36 December 815 590 95 42, 742 •30 •26 1891. January 590 470 488 30, 012 •21 T8 *500 27, 750 *19 *18 March .1 360 285 316 19j 434 •13 •12 April 2, 720 360 1,082 64, 379 •45 •40 May 7, 480 1,855 5, 227 321,460 224 1-93 June 8, 975 6, 685 7, 592 451, 724 3T3 2-81 Estimate. 348 HYDROGRAPHY OF THE ARID REGIONS, Cache la Poudre Creelc above Fort Collins, Colorado. [Drainage area, 1,060 square miles.] • Month. Discharge. Total for month. Run-off. Max. Min. Mean. Depth. Per sq. m. 1884. Second-ft. Second-ft. Second-ft. Acre-ft. Inches. Second-ft. March 15 to 31 92 48 67 4, i20 •07 •06 April 707 64 219 13, 030 •23 •21 May 4,610 453 2,537 156, 025 2-77 2-39 June 5,011 3, 473 4, 812 280, 314 5-08 4-54 July 3, 970 862 2, 144 131,856 2-33 2-03 August. 1.231 423 792 48, 708 •86 •75 September 446 230 305 18, 147 •32 •29 October 1 to 16 224 195 205 12, 607 •22 19 1885. April 4 to 30 822 241 447 26, 596 •47 ■42 May 1,592 954 1,419 87, 268 1-55 1 34 J une 3,857 2. 235 2, 910 173, 145 3-07 275 July 3, 186 1,076 3, 186 195, 939 3-46 301 August 1. 116 369 656 40, 344 •71 •62 September 386 214 272 16, 184 ■29 •25 October 1 to 10 210 202 203 12, 484 •22 •19 1886. April 27 to 30 446 369 405 24, 097 •43 •38 May 2, 659 404 1, 309 80, 403 1-42 1-23 June 2, 584 1,247 1,876 111,622 1-97 1-77 J uly 1, 175 392 717 44, 095 .78 •68 August 1, 475 232 338 20, 787 •37 •33 September 284 115 185 11,007 ■19 17 October 133 120 129 7, 933 ■14 12 1887. May 18 to 29 2, 380 1, 150 1,822 112, 053 1-99 1-72 June 14 to 30 1,970 1,050 1,401 83, 360 1-47 1-32 J uly 1,260 410 735 45, 202 •80 •69 August 430 240 307 18, 880 •33 ■29 September 300 110 175 10, 412 •18 •17 1888. April 350 100 181 10, 769 •19 •17 May 790 250 483 29, 704 •53 ■46 June 1,490 680 1,113 66, 223 117 105 J uly 690 260 420 25, 830 •46 •40 August 500 140 213 13. 100 •23 ■20 September 180 70 109 6, 485 •11 ■10 1889. January 342 71 151 9, 280 16 ■14 February 198 69 106 5, 880 10 •10 March 125 41 46 2 830 •05 ■04 April 342 48 113 6, 730 •12 11 May 1,886 215 649 39, 900 •71 •61 June 1.960 837 1,338 79, 500 1-41 1-26 July 844 271 514 31, 600 .56 •48 August 455 67 187 11, 500 •20 •18 September 75 56 67 3, 990 •07 06 October 92 55 69 4,240 •08 •06 November 122 46 88 5,240 ■09 •08 December 89 33 64 3,940 ■07 06 1890. January 101 46 82 5, 043 •09 •08 February 138 37 79 4,384 •08 •08 March 126 47 85 5, 227 •09 •08 April 481 71 200 11,900 •21 •19 May 1,710 436 1,044 64, 206 1-13 •99 Juue 1,804 1,016 1,280 76, 158 1-35 1-21 July 1,025 336 649 39, 950 •71 ■61 August 404 150 287 17, 650 ■31 •27 September 183 58 103 6,130 •11 ■10 October 118 55 80 4,925 09 •08 November 89 41 61 3, 630 •07 •06 70 4, 305 ■08 •07 1891. * January 150 49 95 5, 842 ■10 •09 February 138 55 75 4, 162 07 •07 March 73 42 61 3, 751 07 06 April 416 48 154 9, 163 16 14 May 2, 080 416 1,162 71. 463 1-26 110 NEWELL.] RIVER DISCHARGES BY MONTHS. 349 Arkansas River at Canyon City, Colorado. [Drainage area, 3,060 square miles.] Month. Discharge. Total for mouth. Run-ofl'. Max. Min. Mean. Depth. Per sq.m. 1888. Second-ft. Second-ft. Second-ft. Acre-ft. Inches. Second-ft. *400 24, 600 15 •13 February "500 27, 750 •17 •16 *600 36, 900 •22 •20 *1, 000 59, 500 •36 *33 May 1,570 1,280 li 440 88, 500 •54 •47 Juiie 2, 760 1, 120 2,090 124, 300 ■76 •68 July 1,870 850 1,350 83, 000 •51 •44 August 1,100 800 932 57, 300 •35 •30 September 850 430 605 36, 000 •22 •20 ; 500 30, 750 T9 T6 *500 29’ 750 •18 T6 *400 24, 600 •15 T3 1889. *300 18, 450 •11 TO *300 16, 620 TO TO *300 18, 450 •11 TO April 17 to 31 438 214 300 17, 850 •ii TO May 1,960 324 600 36, 900 ■23 •20 J une 2,010 1,002 1,374 81, 753 •50 *45 July 1. 150 290 602 37, 023 •23 •20 August 2, 620 243 340 20, 910 •13 Tl September 258 190 220 13, 090 •08 •07 October 284 190 223 13,715 •08 •07 November 335 243 299 17, 790 T1 TO December 438 274 335 20, 602 •13 Tl 1890. January 494 18o 310 19, 065 •12 TO February 446 250 363 20, 146 •12 •12 March 391 180 320 19, 683 •12 TO April 980 200 477 28, 381 •17 T6 May 3, 270 841 2, 090 128, 535 •79 •68 June 3,260 2, 068 2,611 155, 354 •95 •85 July 2, 132 920 1,571 96, 616 •59 •51 August 1,425 580 670 41, 205 •25 •22 September 625 455 519 30, 850 •19 •17 October 605 505 531 32, 650 ■20 •17 November 555 480 522 31,060 •19 T7 December 580 455 502 30, 900 T9 TO 1891. January 505 325 431 26, 506 16 •14 February 580 365 474 26, 307 T6 T5 March 685 530 586 36, 039 •22 •19 April 1, 600 580 857 50, 992 •31 •28 May 3, 370 1,340 2,012 123, 738 . -76 •66 June 4, 230 1,600 3, 291 195, 814 1-20 1-07 Bio Grande at Del Norte , Colorado. [Drainage area, 1,400 square miles.] 1889. October 11 to 31 November December 1890. January February March April May June July August September October November December 1891. January February March April May June 345 214 278 17, 097 •23 •20 364 290 319 18, 980 •25 •23 364 200 281 17, 281 •23 •20 1,000 326 552 33, 948 ■45 ■39 896 745 796 44, 178 •59 •57 842 404 487 29, 950 •40 •35 1,380 404 913 54, 323 •73 •65 5, 930 1,990 4, 331 266, 356 357 3-09 5, 555 2, 550 3,807 226, 516 3-03 2-72 2, 260 862 1,515 93, 172 1-25 1-08 930 450 612 37, 638 •50 •44 450 326 383 22, 800 •31 •27 862 307 470 28, 900 •39 •34 610 345 478 28, 500 •38 •34 670 475 565 34, 750 •46 •40 1,320 670 990 60, 885 •81 •71 1,410 1, 193 1,294 71, 817 •96 •92 1,460 930 1,280 78, 720 1-05 •91 3,160 796 1,410 83, 895 1T2 1-01 5,650 1, 860 3, 285 202, 027 2-70 2-34 5, 555 2,190 4, 146 246, 687 3-31 2-96 350 HYDROGRAPHY OF THE ARID REGIONS. Rio Grande at Embudo, New Mexico. [Drainage area, 7,000 square miles.] Month. Discharge. Total for Run-off. Max. Min. Mean. month. Depth. Per sq. m. 1889. Second-ft. Second-ft. Second-ft. Acre ft. Inches. Second-ft. January 495 379 431 26, 506 •07 •06 February 576 420 473 26, 251 •07 •07 March 1,042 537 784 48,216 13 •11 April 4,420 970 2, 261 134, 530 •36 •32 May 5,075 2, 443 3,430 210, 945 •56 •49 June 5, 660 1,390 2, 922 173, 859 •47 •42 July 1, 105 230 471 28, 966 ■07 ■07 August 253 181 206 12, 669 •03 •03 September 264 184 212 12, 614 ■03 •03 October 324 243 283 17, 404 ■05 •04 November 507 253 366 21, 777 •06 •05 December 1890. 610 364 542 33, 333 09 •08 January 617 260 437 26, 875 •07 ■07 February 670 344 553 30, 691 •08 •08 March 1,044 330 682 41, 943 'll TO April 3, 220 842 2, 083 123, 938 ■33 •30 May 6, 071 2, 060 4,960 305, 040 •82 •71 June 5, 740 2, 768 4, 107 244, 306 •65 •59 July 2,640 920 1,593 97, 969 •26 •23 August 1, 134 636 814 50, 061 T3 T2 September 1,044 496 545 32, 400 •09 ■08 October 606 523 562 34, 600 •09 •08 November 699 550 616 36, 650 TO •09 December 1891. 660 636 648 39, 850 T1 •09 January 666 550 586 36, 039 TO ■08 Febiuary 1, 000 550 616 34, 182 •09 •09 March 1,450 735 917 56, 395 T6 •13 April 5, 690 735 2, 370 141, 015 •38 •34 May 8,550 4,520 5, 965 306, 847 •98 •85 June 6, 340 4, 325 5, 040 299, 880 ■80 •72 Rio Grande' at El Paso, Texas. [Drainage area, 30,000 square miles]. May 10 to 31 June July August September . . October November . . December... 1889. 4, 705 2, 060 4, 460 660 930 252 3, 116 2, 638 237 0 0 0 0 71 191? 634 156, 961 14. 575 0 0 0 0 4,366 •120 •098 •009 0 0 0 0 •003 •104 •090 •007 0 0 0 0 •002 1890. January February March April May June July August September October November December 280 458 1, 140 4,108 7, 200 7,200 2, 355 2,497 660 616 610 610 126 108 45 470 3, 495 2, 925 235 170 40 40 40 430 196 290 424 2, 190 5, 771 4,404 854 734 176 65 284 535 12, 054 16, 095 26, 076 130, 305 354, 916 262, 038 52, 521 45, 141 10, 470 4, 000 16, 950 32, 900 •008 •010 •016 •081 •221 •164 •033 •028 •006 •003 •011 ■020 •007 •010 •014 •073 •190 •147 •028 •024 •006 •002 •009 ■018 1891. January February March April May June 715 2, 640 4, 635 8,625 16, 620 8, 340 140 470 470 1,040 8,340 5,045 451 809 1,866 4, 265 11, 852 6, 714 27, 736 44, 899 114.759 253, 767 726, 528 399, 483 •017 •028 •072 159 •454 •249 ■015 •027 •062 •142 •396 •224 NEWELL.] RIVER DISCHARGES BY MONTHS. 351 Truckee River at Vista, Nevada. [Drainage area, 1,519 square miles.] Month. Discharge. Total for month. Runoff. Max. Min. Mean. Depth. Per sq. m. 1890. Second-ft. Second-ft. Second-ft. Acre-ft. Inches. Second-ft. April 20 to 30 5. 610 3. 730 4, 496 267, 512 3-30 2-96 May 7,510 3, 200 5, 990 368, 385 4-55 3-94 June 6, 710 3, 115 4, 162 247, 639 306 2-74 July 3, 730 1,185 2, 198 135, 177 1-67 1-45 August 1, 152 750 952 58, 548 •72 •63 September 825 570 682 40, 579 •50 *45 October 1,030 490 742 45. 633 •56 •49 November 825 400 765 45, 517 •56 •50 *750 46, 125 •57 *49 1891. *700 43, 050 •46 February *650 36, 075 ■44 •43 *650 39, 975 *50 •43 April 3, 115 570 1,523 90, 618 112 1-00 May 3, 285 1,990 2, 765 170, 047 2-10 1-79 Juiie 2, 730 1, 280 1,905 113, 347 1-39 1-25 * Estimate. East Carson River at Rodenbahs, Nevada. [Drainage area, 414 square miles.] 1890. April 7 to 30 1,565 752 1,026 61, 047 2-76 2-48 May 4 to 31 4,260 1,315 2, 654 163, 221 7'38 641 June 3. 900 1,745 2, 430 144, 585 6-55 5-87 J uly 2, 780 750 1,789 110, 000 4-98 4-32 August 875 437 597 36, 750 1-66 1-44 September 437 400 415 24, 700 1-12 1-00 October 390 385 386 23, 740 1-07 •93 November 385 380 384 22, 850 1-04 •93 December 400 375 379 23, 300 1-06 •92 1891. January 395 385 388 23, 862 1-08 •94 February 715 377 402 22, 311 101 •97 March 1,650 390 783 48, 154 2-18 1-89 April 590 410 452 26. 894 1-22 1-09 May 1,884 1,010 1,445 88, 867 4-02 349 June 1,884 565 1,328 79,016 3-58 3-12 West Carson River at Woodford, California. [Drainage area, 70 square miles.] 1890. April 9 to 30 448 145 284 16, 898 4'56 4-06 May 924 318 657 40, 405 10-83 940 June 1. 284 448 614 36, 533 9-79 8-77 July 606 252 380 23, 370 6-27 5-43 August 240 90 135 8, 300 223 1-93 September 86 70 75 4, 080 1-09 1-07 October 78 54 67 4, 120 1-10 •96 November 58 46 49 2,915 ■78 ■70 December 58 42 53 3, 261 •87 •76 1891. J anuary 62 46 52 3,198 ■86 •74 February 58 42 48 2.604 •71 •69 March 68 50 61 3, 758 1-01 ■87 April 384 62 127 7. 556 2-02 1-82 May 740 300 534 32, 820 8-79 7-62 June 456 260 338 20, 111 5-38 4-83 352 HYDROGRAPHY OF THE ARID REGIONS, Bear River at Battle Creek, Idaho. [Drainage area, 4,500 square miles.] Month. Discharge. Total for month. Run-off. Max. Min. Mean. Depth. Persq. m. 1889. Second-ft. Second-ft. Second-ft. Acre-ft. Inches. Second-ft. October 11 to 31 430 300 355 21, 832 ■09 •07 November 830 430 487 28, 976 •12 •11 December 735 350 565 34, 747 •14 •13 1890. January 1, 255 270 875 53, 812 •22 •19 February 2, 040 600 809 4,490 •18 ■18 March 2, 040 780 1,271 78, 166 •32 •28 April 3, 960 2, 170 2, 978 177, 191 •74 •66 May 5,980 3, 960 5, 199 319, 738 1-33 1-60 June 5, 980 2, 300 4,074 245, 000 1-02 •91 July - 2,170 1,200 1,582 97, 293 •40 •35 August 1,200 880 1,000 61, 500 •26 •22 September 880 780 843 50, 150 •21 •19 October 880 780 854 52, 500 •22 •19 N ovember 880 780 783 46, 600 •19 •17 December 780 690 748 46, 000 •19 •17 1891. January 690 690 690 42, 435 •18 •15 February 780 43, 290 •18 •17 March 880 780 790 48, 585 •20 •17 April 2, 950 780 1,623 96, 509 •40 •36 May 3, 030 2, 440 2,652 163, 098 ■68 *59 June 2, 870 1,660 2, 245 133, 578 •56 •50 Bear River at Collinston, Utah. [Drainage area, 6,000 square miles.] June July 24 to 31 August September . . October November . . December. . . January February March 2 to 31 April May J une July August September . . . October November ... December January February . . . March April 1 to 11 May June *800 47, 600 •15 •13 385 340 362 22, 263 •07 •06 450 385 417 25, 645 •08 •07 610 450 509 30, 285 •09 •08 825 610 728 44, 772 ■14 •12 1,000 780 848 50, 456 16 •14 1, 925 955 1,395 85, 792 •27 •23 *1, 500 92, 250 •29 •25 *1, 000 55, 500 •17 •17 4, 850 1, 100 3, 188 196, 062 •61 •53 6, 680 3,600 4,953 294, 703 •92 •83 8, 220 6, 890 7, 924 487, 326 1-52 1-32 7, 940 4,440 6, 234 270, 923 116 1-04 4,230 2, 060 3,250 199, 875 •62 •54 2, 060 1,545 1,754 107, 871 •34 •29 1,425 1,310 1,3*4 80, 050 •25 •22 1,665 1, 365 1,544 95, 000 ■30 •26 1,425 1,365 1,403 83, 5d0 •26 •23 1,545 1, 000 1,243 76, 500 •24 •20 1, 000 61, 500 T9 •17 2,200 825 li 308 72, 594 •22 •22 2, 340 1,425 1,766 108, 710 •34 •29 5,000 1,665 2, 729 162, 375 •51 •45 5,000 4 020 4,569 280, 993 •88 •76 4, 720 2, 480 3,595 213, 902 •67 •60 Estimate. NEWELL.] RIVER DISCHARGES BY MONTHS. 353 Oqden River at Powder Mills, Utah. [Drainage area, 360 square miles.] Month. Discharge. Total for Run-off. Max. Min. Mean. month. Depth. Per sq. m. 1889. Second-ft. Second-ft. Second-ft. Acre-ft. Inches. Second ft. August 9 to 31 60 40 50 3,075 •16 T4 September 70 50 52 3,094 •16 T4 October 145 70 89 5, 473 •28 •24 November 253 60 105 6, 247 •33 •29 December 735 145 421 25. 891 1-35 117 1890. January 510 289 382 23, 493 1-22 106 February 1,364 399 680 37, 740 1-97 1-89 March 1,401 362 978 60, 147 3-13 2-72 April 1,919 1,068 1,449 86, 215 4-49 4'02 May 2, 178 1,475 1,818 111,807 5'82 505 J une 1,438 624 910 54, 145 2-82 253 J uly 624 326 458 28, 167 1-47 1-27 August 473 215 312 19, 188 1-00 •86 September 235 195 206 12, 260 •64 •57 October 326 215 265 16, 290 •85 •74 November 267 235 255 15,180 •79 •71 December *240 14, 760 •77 •67 * Estimate. Weber River in canyon above Uinta, Utah. [Drainage area, 1,600 square miles.] 1889. October 13-31 290 130 181 11,131 T3 ■11 November 290 160 208 12, 376 T4 T2 December 815 200 430 20, 445 •31 •27 1890. J anuary 815 290 457 28, 105 •33 ■29 February 1,400 200 547 30, 358 •36 •34 March 2, 130 200 1,091 67, 096 ■79 •68 April 4,280 970 2, 184 129, 948 1-52 1-36 May 5,465 3,470 4, 528 278, 472 3-26 283 J une 3, 635 1,220 2, 017 120,011 1-41 1-27 July 1,220 290 549 33, 763 ■40 •34 August 450 200 280 17, 220 •20 T8 September 290 240 265 15, 750 T8 •17 October 450 200 331 19, 850 •22 •21 November 340 290 298 17,720 •21 T9 December 340 240 290 17, 830 •21 T8 1891. January 450 290 303 18, 634 •23 T9 February 1,220 290 461 25, 586 •30 •29 March 1,220 450 025 38, 437 •45 •39 April 2,420 520 1,502 89, 369 1-05 ■94 May 4, 655 1,940 2, 752 169, 250 1-98 1-72 June 2, 225 1, 135 1,621 96, 449 1T3 101 -23 12 GEOL.. PT. 2 - 354 HYDROGRAPHY OF THE ARID REGIONS, Provo Eiver above Provo , Utah. [Drainage area, 640 square miles.] Month. Discharge. Total for month. Run- off. Max. Min. Mean. Depth. Persq. m. 1889. Second-ft. Second-ft. Second-ft. Acreft. Inches. Second-ft. July 27 31 150 149 150 9, 225 •27 •23 August 149 144 145 8,917 •26 •23 September 174 144 150 8,925 •26 •23 October 200 174 180 11, 070 ■32 •28 November 280 200 224 13, 328 -39 -35 December 630 240 384 23, 616 •69 •60 1890. January ; 700 200 305 18, 751 •55 •48 February 564 280 377 20, 923 •61 -59 March 700 240 519 31, 990 •94 -81 April 1,240 500 840 49, 980 1-46 1-32 May 2, 180 1,316 1, 926 118, 450 347 301 June 2, 260 440 1.184 70, 448 2-06 1-85 July 440 280 314 19,311 ■56 49 August 280 240 252 15, 498 •45 -39 September 280 240 244 14, 520 •43 •38 October 330 280 304 18, 700 •55 •48 November 330 280 303 18, 020 •53 -47 December 330 240 293 18, 020 •53 •46 1891. January 280 240 255 15, 682 •46 •40 February 500 280 311 17, 240 •50 •48 March 1,316 280 492 30, 258 •89 •77 April 930 280 478 28, 430 •83 •75 May 1, 704 851 1,226 75, 399 2-21 1-92 June 1,470 851 1,190 70, 805 2-07 1-86 Spanish Fork in canyon , Utah. [Drainage area, 670 square miles.] 1889. September 70 45 50 2, 975 •08 •07 October 70 50 62 3, 813 11 ■09 November 70 45 63 3,153 •09 •08 December 70 50 67 4,120 12 •10 1890. January 230 50 68 4, 182 ■12 •10 February 95 50 76 4, 218 •12 -11 March 355 50 143 8, 794 ■25 •21 April 770 150 387 23, 026 •64 •58 May 1,040 355 777 47, 785 1-34 1-15 June 355 110 205 12, 197 •34 •31 July 590 82 114 7, 011 •20 ■17 August 82 50 64 3, 837 11 •10 September 95 50 63 3, 750 •10 •09 October 95 50 64 3, 938 11 •10 November 50 50 50 2, 975 •08 •07 December 50 50 50 3. 075 •09 •07 NEWELL.] RIVER DISCHARGES BY MONTHS. 355 Sevier Fiver at Leamington, Utah. [Drainage area, 5,595 square miles.] Month. Discharge Total for Run-off. Max. Min. Mean. mouth. Depth. Fersq. m. 1889. Second -ft. Second-ft. Second -ft. Acre-ft. Inches. Second-ft. August 23 to 31 60 40 48 2, 952 •01 •008 September 80 48 53 3,153 ■01 •009 October 160 48 111 6, 826 •02 •019 November 444 210 274 16, 303 •05 •049 December 1890. 526 280 395 24, 292 •08 •071 January 1,058 280 625 38, 437 •13 T1 February 1,140 567 713 39. 571 13 13 March 690 567 630 38,745 T3 T1 April 976 608 726 43, 197 14 T3 May 2, 329 976 1, 705 104, 857 •35 •31 June 2, 206 649 1,250 74, 375 ■25 •22 J uly 649 185 346 21, 279 •07 •06 August 185 150 153 9.409 ■03 •03 September 185 150 157 8, 345 •03 •03 October 362 185 310 19, 050 06 •06 November 403 321 373 22, 100 •07 •07 December 1891. 649 403 509 31, 320 1-05 •09 January 772 649 735 45, 202 15 13 February 772 772 772 42, 846 . T4 14 March 772 526 618 38, 007 13 11 April 608 526 503 29, 928 ■10 •09 May 1,386 608 1, 114 68,511 •23 •20 June 1,140 567 952 56, 644 T9 T7 Henry Fork in canyon, Idaho. [Drainage area, 931 square miles.] 1890. -1,200 738, 000 1-49 1-29 February *1,250 69, 375 1-40 1-35 *1, 300 79, 950 1-61 1-40 April 6 to 30 4, 920 1, 120 1, 875 111' 562 2-25 2-01 May 7,710 2, 750 4,580 281, 670 5-67 4-92 J une 2, 890 1,860 2, 270 135, 065 2-72 244 1,860 1,450 1,550 95, 325 1-92 1*66 August 1,450 1,450 1,450 89, 175 1-80 1-56 September 1,450 1,280 1,314 78, 183 1-57 1-41 October 1,280 1, 280 1,280 78, 720 1-59 1-38 November 1,280 1,280 1,280 76, 150 1-55 1-37 December 1, 280 1,280 1,280 78, 720 1-59 1-38 1891. January 1,280 1,280 1,280 78, 720 1-59 1-38 February 1,280 1,280 1,280 71, 040 1-43 1-38 March 1,280 1,280 1,280 78, 720 1-59 1-38 April 2, 600 1,280 1, 516 90, 505 1-83 1-63 May 3, 180 1, 640 2, 184 134, 316 2-71 233 June 2, 215 1,450 1,801 107, 160 2T6 1 94 Estimate. 356 HYDROGRAPHY OF THE ARID REGIONS. Falls River in canyon , Idaho. [Drainage area, 594 square miles.] Month. Discharge. Total for month. Run-off. Max. Min. Mean. Depth. Per sq. m. 1890. Second -ft. Second-ft. Second-ft. Acre-ft. Inches. Second-ft. April 25 to 30 2, 480 1,250 1,730 102, 935 3-25 2-92 May 4,440 2, 630 3, 342 205, 533 6-49 5-63 J une 4, 050 2, 030 2,706 161, 007 5'08 4‘56 July 2,630 1,030 1,669 102, 643 3-20 2-81 August 1,140 840 971 59, 717 1-82 1-63 September 930 660 774 46, 000 T45 1-30 October 750 570 660 39, 950 1-26 1-09 November 570 480 541 30, 360 •95 ■86 December 480 480 520 29, 520 •93 •81 1891. January 590 450 509 31, 304 •99 •86 *450 24, 975 •79 •76 *450 27, 675 *87 *76 April 1, 140 450 606 36; 057 1*14 102 May 2, 790 1,030 1, 765 108, 547 3-43 2-98 June 2, 180 1,370 1,681 100, 019 3-17 2-85 * Estimate. Teton River at Chase’s ranch , Idaho. [Drainage area, 967 square miles.] 1890. 1,295 4.445 545 740 44, 030 167, 895 167, 314 130, 995 41,700 27, 500 •85 •77 May 1,545 1,925 2,730 3*26 2*82 4, 065 2,950 935 2, 812 2, 130 3*26 2-91 935 2-54 2-20 510 678 •81 *70 510 450 462 •53 •48 510 450 475 29, 200 •49 450 450 450 26, 700 •52 •46 510 450 459 28, 200 24, 600 22, 807 27, 675 37, 485 ■55 •47 1891. *400 •48 *41 475 450 465 •56 •47 450 450 450 ■54 •47 935 450 630 •72 *65 May 2,360 2, 360 720 1,402 86, 223 98, 829 1-66 1-45 1,295 i;e6i 1-91 1-72 Estimate. NEWEIA.] RIVER DISCHARGES BY MONTHS, 357 Snake River at Eagle Rock or Idaho Falls, Idaho. [Drainage area, 10,100 square miles.] Month. Discharge Total for month. Run-oft. Max. Min. Mean. Depth. Persq. m. 1889. Second-ft. Second-ft. Second -ft. Acre-ft. Inches. Second-ft. July 8,646 3. 174 5.184 318,816 •59 •51 August 3, 130 2, 286 2, 594 159, 654 •30 •26 September 2, 508 2, 286 2, 300 136, 850 •25 •23 October 2, 730 2. 286 2. 425 149, 137 •28 •24 November 2,952 2, 508 2, 737 162, 851 •30 •27 December 2, 730 2, 508 2,601 159, 961 •30 •26 1890. *2, 000 123, 000 •23 •20 *2, 000 111, 000 •21 •20 *2, 000 123, 000 *23 *20 April 15, 000 2, 900 5; 702 339, 269 •63 •57 May 49. 350 16, 900 35,606 2, 189, 769 4-06 352 June 50, 450 24, 930 34, 870 2, 074, 765 3'85 345 July 28, 800 10, 700 19, 970 1,228, 155 2-28 1-98 August 10, 350 6, 250 7,875 484, 312 •90 •79 September 5, 950 4,350 4,934 293, 800 •54 •48 October 4, GOO 4, 350 4, 552 280, 000 •52 •45 November 4,350 3, 900 4, 207 250, 000 •47 •42 December •3, 900 239, 850 •45 •39 + Estimate. Omjliee River at Rigsbys, Oregon. [Drainage area, 9,875 square miles.] 1890. March 26 to 31 7. 350 5, 190 6, 140 377, 610 •72 •62 April 8, 225 5, 395 6, 558 390, 201 •74 •66 May 11,230 3, 010 5, 913 363, 649 •69 •60 June 2. 850 620 1,403 83, 478 ■16 •14 July 560 200 343 21, 094 •04 •03 August 200 170 179 11. 108 •02 •02 September 170 170 170 10,115 •02 •02 October 170 170 170 10, 455 •02 •02 November 280 221 221 13. 150 •02 •02 December 360 280 309 19, 004 •04 •03 1891. January 400 360 320 22, 140 •04 •04 February 3, 265 450 932 51, 726 •10 •09 March 4, 335 2.600 3, 313 203, 649 •39 •34 April 10. 000 2, 900 4.984 296, 548 ■56 •51 May 4,600 2. 075 3,114 191,511 ■36 •31 June 2,150 500 1,267 75, 386 14 13 358 HYDROGRAPHY OF THE ARID REGIONS. Malheur River at Vale, Oregon. [Drainage area, 9,900 square miles.] Month. Discharge Total for P.UI i-off. Max. Min. Mean. month. Depth. Per sq.m. 1890. Second-ft.' Second-ft. Second-ft. Acre-ft. Inches. Second-ft. March 20 to 31 4, 445 1,840 2, 912 179, 088 •34 ■29 April 3, 450 2, 180 2, 770 164.815 •31 •28 May 2, 890 590 1.627 100, 060 .19 •16 June 520 120 254 15, 113 •03 •02 J uly 90 25 43 2, 644 •005 •004 August '25 15 17 1.011 •002 •002 September 15 15 15 893 •002 •001 October 62 15 44 2. 705 •005 •004 November 150 70 118 7, 010 •013 •012 Decewbor 1891. 115 62 83 5,105 •009 •008 J anuary 115 70 88 5, 412 •01 ■009 February 2, 820 80 319 17, 704 •03 •03 March 1 , 460 260 703 43, 234 ■08 •07 April 605 325 511 30, 404 •06 •05 May 325 115 217 13, 345 ■03 •02 June 185 45 78 4, 641 •01 •01 Jl'eiser River in canyon, Idaho. [Drainage area, 1,670 square miles.] 1890. March 13 to 31 11,220 7, 060 1,550 5, 773 355, 039 3-99 3-45 April 2. 470 4,792 285, 124 3-20 2-87 May 7, 060 2,610 4,882 300, 243 3-37 2 92 June 2, 470 1,280 1,792 106, 624 1-20 1-07 July 1, 130 220 590 36, 285 •41 •35 August 190 100 138 8,487 •09 •08 September 140 80 103 6,135 •07 •0.’ October 190 140 166 10, 200 •11 TO November 400 160 222 13, 200 *15 .13 December 480 280 396 24, 350 •28 •24 1891. January 320 190 292 17, 958 •20 T7 February 1, 860 320 678 37, 629 •42 •41 March 9, 300 1,010 2, 855 175, 582 1-97 1-71 April 2, 220 1,260 1,777 105, 731 1-26 1-06 May 1,640 1,010 1,331 81, 856 •93 •80 June 1, 010 500 703 41, 828 •47 •42 MONTHLY PERCENTAGES OF RTJN-OFF. The following table, giving the relative discharges of various streams during each month of the year, has been prepared for the purpose of aiding in approximations of discharge when but one or two meas- urements are available. The table shows the percentage of the aver- age discharge for one month to the total for the year, and from these figures, based on actual measurements, certain inferences may be drawn. The years have been arbitrarily selected, the period being governed largely by the time at which gaugings were begun, and dur- ing which they were carried on. For example, in the first instance in the year from August 1, 1889, to July 31, 1890, the discharge during June was 27-4 per cent of the total discharge of the year, but taking the time from January 1, 1890, to December 31, 1890, the discharge for NEWELL.] PERCENTAGES OF DISCHARGE BY MONTHS. 361 oc o ro ri ti 1' x x ^ ’-p t- ip — m 6 ih « f 1 in © t- i t- n m w r: Oioo-i'^OH'fHi^wofflo^inoL'io 0 nfiTfuhiMrO'^'t-^it-'J'^C'icobbo l>'^l 0 «'^*H 00 ^HTfwup-^C| 0 MC 5 Ot?'lin rtNN-T'WMO^flit'ihrj'NMOOO NMt-^HHI>prtOMOOlflONONI> NWM-^WMOWWt- 00 «b»hw «?000 o ^ tp »n o m o a eo in o ;p •># n is n io o (fiW'^'ihibibib-fiot-do^Ht-ihibAHoro 00 ifl.^OO 3 >?)t'L' 5 OMCffi 05 MHOH 4 -ooc : -^-'C 56 soocb- ; t^-(odoifi'^t : -t-ooo rlHrlfl HHHHr-ir-NMW NNH'OO^MMHNLO^MOONiflffl d 0 © 00 »H|>t--i*C