University of Illinois Bulletin 
 
 Vol. Ill FEBRUARY 1 , 1906 No. 9 
 
 Published Fortnightly by the University. 
 
 Entered at Urbana, Illinois, as second-class matter. 
 
 DRAINAGE -f EARTH ROADS 
 
 IRA O. BAKER 
 
 CIRCULAR NO. 2 OF THE UNIVERSITY OF ILLINOIS 
 ENGINEERING EXPERIMENT STATION 
 
 REPRINTED FOR THE 
 
 Chicago & Alton Railway’s Good Road Train 
 
 FEBRUARY 12. 1906 
 
(®a,5*n 
 
 '13IU 
 
 3 
 
 -~o 
 
 <V 
 
 
 £ 
 
 An Engineering Experiment Station was established at the Uni- 
 versity of Illinois by action of the Board of Trustees, December 8, 
 1903. It is the purpose of the Station to carry on investigations 
 along various lines of engineering and to study problems of im- 
 portance to professional engineers and to manufacturing, railway, 
 constructional, and industrial interests of the state. The labora- 
 tories of the College of Engineering are being equipped with addi- 
 tional apparatus and facilities to further such research work. It is 
 believed that this experimental work will result in contributions of 
 value to engineering science and that the presence of such investi- 
 gations will give inspiration to students and add efficiency to the 
 College of Engineering. 
 
 The publications of the Station consist of Bulletins which con- 
 tain the results of original investigations, and of Circulars which 
 present subjects believed to be of value to those addressed although 
 the matter itself may not be entirely new. 
 
 This Circular is presented to assist the movement for the im- 
 provement of the wagon roads, and it is hoped that it may be help- 
 ful to those having in charge the highways of the state. 
 
 All correspondence concerning the work of the Station should 
 be addressed to the Engineering Experiment Station, Urbana, 
 Illinois. 
 
 r * . L o, r i U 
 
4 
 
 DRAINAGE OF EARTH ROADS. 
 
 Ira O. Baker, Professor of Civil Engineering, University of Illinois; 
 Author of Roads and Pavements, Masonry Construction, Etc. 
 
 Drainage is the most important matter to be considered in either 
 the construction or the maintenance of any form of road, since no 
 road, whether earth, gravel or broken stone, can long remain good 
 without it. Drainage alone will often change a bad earth road to 
 a good one, while the best stone road may be destroyed by the ab- 
 sence of proper drainage. Water is the natural enemy of earth 
 roads, for mixed with earth it makes mud, and mud makes bad 
 going. The rain or snow softens the earth; the horses ’ feet and 
 the wagon wheels mix and knead it; and soon the road becomes 
 impassable mud, which the frost finally freezes, and the second 
 state of the road is worse than the first— for a time at least. 
 Further, if the water is allowed to course down the middle of the 
 road it will wash away the earth, and leave gullies in the surface 
 that must be laboriously filled up by traffic or repairs. No road, 
 however well made otherwise, can endure if water collects or re- 
 mains on it. Prompt and thorough drainage is a vital essential in 
 all road construction, and particularly so for earth roads. 
 
 A perfectly drained road will have three systems of drainage, 
 each of which must receive special attention if the best results are 
 to be obtained. This is true whether the trackway be iron, broken 
 stone, gravel, or earth; and it is emphatically true of earth. These 
 three systems are (1) underdrainage, (2) side ditches, and (3) sur- 
 face drainage. 
 
 1. Underdrainage. 
 
 Any soil in which the standing water in the ground comes at 
 any season of the year within 4 or 5 feet of the surface will be 
 benefited by drainage; that is, if the soil does not have a natural 
 underdrainage, it will be improved for road purposes by artificial 
 subsurface drainage. It is the universal observation that roads 
 in low places which are underdrained dry out sooner than un- 
 drained roads on high land. Underdrained roads never get as bad 
 
as do those not so drained. Underdrainage without grading is 
 better than grading without drainage; and, in general, it may be 
 said that there is no way in which road taxes can be spent to 
 better advantage than in subsurface drainage. Underdrainage is 
 the very best preparation for a gravel or stone road. Gravel or 
 broken stone placed upon an undrained foundation is almost sure 
 to sink (perhaps slowly, but none the less surely), whatever its 
 thickness; whereas a thinner layer upon a drained road-bed will 
 give much better service. Underdrained roads without gravel are 
 better than graveled roads without underdrainage. 
 
 Objects of Underdrainage. 
 
 Many persons seem to think that the sole object of underdrain- 
 age is to remove the surface water, but this is only a small part 
 of the advantages of the underdrainage of roads. There are three 
 distinct objects to be sought by the underdrainage of a wagon road, 
 viz.: (1) to lower the water level in the soil; (2) to aid in drying 
 the ground quickly after a freeze; and (3) to cut off the underflow. 
 
 1. To Lower the Water Level. When rain water falls upon 
 the surface of the ground it sinks into the soil, and continues to 
 flow downward until it reaches soil that is saturated, that is, it 
 flows vertically downward until it reaches the surface of what 
 may be called the underground lake. The most important object 
 of underdrainage is to lower the level of this underground lake. 
 The action of the sun and the breeze will finally dry the surface 
 of the road; but if the foundation is soft and spongy, the wheels 
 will wear ruts and the horses ’ feet will make depressions between 
 the ruts. The first shower fills these depressions with water, and 
 the road is soon a mass of mud. A good road can not be main- 
 tained without a good foundation; and an undrained soil is a poor 
 foundation, but a dry soil can support almost any load. The lower- 
 ing of the surface of saturation not only improved the road by 
 keeping the surface comparatively dry, but also prevents, or greatly 
 reduces, the destructive effect of frost. The injurious effect of 
 frost is caused entirely by the presence of water, and the more 
 water there is in the road-bed the greater the injury to the road. 
 The water expands on freezing, the surfkce of the road is up- 
 heaved, and the soil is, made porous; when thawing takes place, 
 
6 
 
 the ground is left honeycombed and spongy, ready to settle and 
 sink, and under traffic the road “breaks up.” If the road is kept 
 dry, it will not break up. Underdrainage can not prevent the sur- 
 face of the road from becoming saturated with water during a 
 rain, but it is the best means of removing the surplus water, thus 
 drying the surface and preventing the subsequent heaving by frost. 
 
 That frost is harmless where there is no moisture, is shown on 
 a large scale in the semi-arid regions west of the Mississippi River. 
 The ground there is normally so dry that during the winter when 
 it is frozen, cracks form half an inch or more wide, owing to 
 the drying and consequent contraction of the soil, which shows 
 that there is no expansion by the freezing of water in the soil; 
 and therefore there is no heaving or disturbance by frost. In this 
 region houses are often built on the very surface of the ground, 
 and no trouble is ever experienced by the action of frost. But in 
 Illinois the surface soil is frequently saturated; and therefore it is 
 necessary to underdrain to prevent the heaving of the frost, and 
 the consequent “breaking up” of the roads. 
 
 2. To Aid in Drying the Ground Quickly After a Freeze. 
 
 When the frost comes out of the ground in the spring, the thawing 
 is quite as much from the bottom as from the top. If the land is 
 underdrained, the water when released by thawing from below will 
 be immediately carried away, which is particularly important in 
 road drainage, since the foundation will then remain solid and the 
 road itself will not be cut up. Underdrainage will usually prevent 
 the “bottom dropping out” when the frost goes out of the ground. 
 This effect of underdrainage is much more important than many 
 seem to think, but a little observation will show its value. 
 
 3. To Cut Off the Underflow. A third, and sometimes a very 
 important, object of subdrainage is to remove what may be called 
 the underflow. In some places where the ground is comparatively 
 dry when it freezes in the fall, it will be very wet in the spring 
 when the frost comes out— surprisingly so considering its dryness 
 before freezing. The explanation is that after the ground freezes, 
 water rises slowly in the soil by the hydrostatic pressure of the 
 water in higher places; and if it is not drawn off by underdrainage, 
 it saturates the subsoil and rises as the frost goes out, so that the 
 ground which was comparatively dry when it froze is practically 
 saturated when it thaws. 
 
7 
 
 
 
 
 The Method of Underdrainage. 
 
 ^ ^6 
 
 
 The Tile. The best and cheapest method of securing under- 
 drainage is to lay a line of porous or farm tile 3 or 4 feet deep 
 on one or both sides of the roadway. The ordinary farm tile 
 is entirely satisfactory for road drainage. It should be uniformly 
 burned, straight, round in cross section, smooth inside, and have 
 the ends cut off square. Tile may be had from 3 to 30 inches in 
 diameter. The smaller sizes are usually a foot long, and the larger 
 sizes are 2 or 2-^ feet long, but usually the former. The cost of 
 tile free on board cars at almost any railroad station in Illinois is 
 about as given in Table 1, although the prices may be a little 
 higher or a little lower, depending upon the demand at the factory 
 or upon the freight rate. Y’s for connections can be had at most 
 factories, but they cost four or five times as much as an ordinary 
 tile. With patience and a little experience ordinary tile can be cut 
 to make fairly good connections. 
 
 Before the introduction of tile for agricultural drainage, it was 
 customary to secure underdrainage by digging a trench and deposit- 
 ing in the bottom of it logs or bundles of brush, or a layer of 
 broken stone; or a channel for the water was formed by setting 
 a line of stones on each side of the trench and joining the two 
 with a third line resting on these two. Apparently it is still the 
 practice in some localities to use such substitutes for ordinary 
 drain tile. Tiles are better, since they are more easily laid and 
 are less liable to get clogged. Tiles are cheaper in first cost, even 
 when shipped considerable distances by rail, than any reasonably 
 good substitute, and the drains are much more durable. 
 
 Tiles are laid simply with their ends in contact, care being taken 
 to turn them until the ends fit reasonably close. In some localities 
 there is apparently fear that the tile will become stopped by fine 
 particles of soil entering at the joints, and consequently it is specified 
 that the joint shall be covered with tarred paper or something of 
 the sort; but in the Mississippi Valley, where immense quantities 
 of tile have been laid, no such difficulty has been encountered. With 
 a very slight fall or even no fall at all, tiles will keep clean, if a 
 free outlet is provided and if they are not obstructed by roots of 
 trees— particularly willow. 
 
 In some localities it is apparently customary to use collars 
 around the ends of the tile to keep them in line. If the bottom of 
 
8 
 
 TABLE I. 
 
 Cost and Weight of Drain Tile. 
 
 SIZE 
 
 Price per 
 1,000 feet 
 
 Weight 
 per foot 
 
 Average Car Load 
 
 Pricee of 
 Connec- 
 tions 
 
 No. pieces 
 
 Rods 
 
 4-inch 
 
 tile 
 
 $ 15.00 
 
 6 lbs. 
 
 6,500 
 
 390 
 
 8 .10 
 
 5 “ 
 
 4 
 
 21.00 
 
 8 “ 
 
 5,000 
 
 300 
 
 .12 
 
 6 “ 
 
 4 4 
 
 27.00 
 
 11 “ 
 
 4,000 
 
 240 
 
 .14 
 
 7 “ 
 
 4 4 
 
 36.00 
 
 14 “ 
 
 3,000 
 
 180 
 
 .15 
 
 8 “ 
 
 4 4 
 
 48.00 
 
 18 “ 
 
 1,200 
 
 144 
 
 .25 
 
 10 “ 
 
 4 4 
 
 66.00 
 
 25 “ 
 
 800 
 
 96 
 
 .35 
 
 12 “ 
 
 4 4 
 
 95.00 
 
 33 “ 
 
 500 
 
 60 
 
 .60 
 
 14 “ 
 
 4 4 
 
 150.00 
 
 43 “ 
 
 400 
 
 48 
 
 .60 
 
 15 “ 
 
 4 4 
 
 165.00 
 
 50 “ 
 
 300 
 
 36 
 
 .70 
 
 16 “ 
 
 4 4 
 
 190.00 
 
 53 “ 
 
 250 
 
 30 
 
 .80 
 
 18 “ 
 
 
 265.00 
 
 70 “ 
 
 200 
 
 24 
 
 1.00 
 
 20 “ 
 
 4 4 
 
 335.00 
 
 83 “ 
 
 166 
 
 20 
 
 1.25 
 
 22 “ 
 
 4 4 
 
 4C0.00 
 
 100 “ 
 
 160 
 
 19 
 
 1.50 
 
 24 “ 
 
 4 4 
 
 450.00 
 
 112 “ 
 
 150 
 
 18 
 
 2.00 
 
 80 “ 
 
 4 4 
 
 750.00 
 
 192 “ 
 
 65 
 
 10 
 
 3.00 
 
 the trench is made but little wider than the diameter of the tile, 
 or if a groove is scooped out in the bottom of the trench to fit the 
 tile, no difficulty need be apprehended from this source. 
 
 The Size of Tile. The following formula is sometimes employed 
 to determine the amount of water removed by a tile ; but the 
 formula is only approximate, and results obtained with it are only 
 mathematical guesses, since we can not know with any certainty 
 the maximum rate of rainfall, the duration of the maximum rate, 
 the permeability of the soil, the amount of water retained by the 
 soil, the effect of surface water flowing onto the road from higher 
 ground, the area to be drained, etc. The formula is useful only 
 in a locality where there is no local experience with tile; and its 
 chief value consists in showing the relation between capacity and 
 grade, and the effect of a variation in the diameter of the tile. 
 
 The formula is : 
 
 A— 1 . 9 pp 5 
 
 in which A is the number of acres for which a tile having a 
 diameter of d inches and a fall of f feet in a length of 1 feet will 
 remove 1 inch in depth of water in 24 hours. 
 
 The object of underdraining a road is to prevent the plane of 
 saturation from rising so near the surface as to soften the founds 
 tion of the road even during a wet time, and therefore the pro- 
 vision for underdrainage should be liberal; but what will be ado- 
 
9 
 
 quate in any particular case depends upon the amount of traffic, 
 the local conditions, the soil, etc. The best practice in agricultural 
 drainage provides for the removal of 0.5 to 1 inch of water per 
 day; but since the side ditches will assist in removing rain water 
 from the road, it is probable that a provision for the removal of 
 half an inch per day is sufficient for the underdrainage of a road. 
 If there is an underflow of water from higher ground, or if the 
 ground is ‘ 1 springy, ’ ’ then the ordinary provisions for underdrain- 
 age should be increased. 
 
 It is not wise to lay a smaller tile than a 4-inch one, and prob- 
 ably not smaller than a 5-inch. Tiles can not be laid in exact line, 
 and any tilting up of one end reduces the cross section. Again, if 
 there is a sag in the line equal to the inside diameter, the tile will 
 shortly become entirely stopped by the deposit of silt in the de- 
 pression. 
 
 It is sometimes wiser to lay a larger tile than to increase the 
 fall. Again, it may be better to lay a large tile near the surface 
 with smaller fall than to lay small tile deeper with a greater fall. 
 Ordinarily, the deeper the tile the better the drainage, although 
 3Y 2 or 4 feet deep is usually sufficient. 
 
 The Fall. There is no danger of the grade of the tile being 
 too great, and the only problem is to secure sufficient fall. A num- 
 ber of authorities on farm drainage and also several engineering 
 manuals assert that a fall of 2 y 2 or. 3 inches per 100 feet is the 
 lowest limit that should be attempted under the most favorable 
 conditions; but practical experience has abundantly proved that 
 a much smaller fall will give good drainage. In central Illinois 
 and northern Indiana are many lines of tile having falls of only 
 1-6 to 1-4 of an inch per 100 feet which are giving satisfactory 
 drainage; and not unfrequently the ordinary porous tiles laid abso- 
 lutely level directly upon the earth in the bottom of the trench, 
 without collars or other covering over the joints, have given good 
 drainage without trouble from the deposit of sediment. Of course, 
 extremely flat grades are less desirable than steeper ones, since 
 larger tiles must be used, and greater care must be exercised in 
 laying them, and there is more risk of the drain becoming ob- 
 structed; but these extremely flat grades are sometimes all that 
 can be obtained, and such drains abundantly justify the expense 
 of their construction. 
 
10 
 
 If possible at reasonable expense, the grade should be at least 
 2 inches per 100 feet; and should never be less than y 2 inch 
 per 100 feet unless absolutely necessary. On level or nearly level 
 ground, the fall may be increased by laying the tile at the upper 
 end shallower than at the lower. 
 
 Laying the Tile. It is unwise to enter upon any detailed discus- 
 sion of the art of laying the tile. The individual tiles should be 
 laid in line both vertically and horizontally, with as small joints 
 at the end as practicable. Care should also be taken that the tile 
 is laid to a true grade, particularly if the fall is small, for if there 
 is a sag it will become filled with sediment, or if there is a crest 
 silt will be deposited just above it. The drain should have a free 
 and adequate outlet. The end of the line of tile should be pro- 
 tected by masonry, by plank nailed to posts, or by replacing three 
 or four tiles at the lower end by an iron pipe or by a wooden box. 
 
 The prevailing prices for laying tile in loam with clay subsoil 
 is about as follows: for 8-inch tile or less 10 cents per rod for 
 each foot of depth; for 9-inch, 11 cents; for 12-inch, 14 cents; for 
 15-inch, 17 cents; and for 16-inch, 18 cents. To aid in remem- 
 bering the above data, notice that the price is 10 cents per rod per 
 foot of depth for 8-inch tile or less, with an increase of 1 cent for 
 each additional inch of diameter. 
 
 The cost of a mile of 5-inch tile drain is usually from $200 to 
 $250, exclusive of freight on the tile. If there is any considerable 
 amount of work, the above prices for the smaller tile can be re- 
 duced 10 to 20 per cent. A tile drain is a permanent improvement 
 with no expense for maintenance, the benefit being immediate and 
 certain; and therefore it is doubtful if money can be spent on 
 earth roads to better advantage than in laying tile. 
 
 One or Two Lines? Usually a line of tile 2 y 2 to 3 feet deep 
 under the ditch at one side of the road will give sufficient drainage. 
 Some tests made by the Illinois Agricultural Experiment Station 
 (not yet published) seem to indicate that one line will give fairly 
 good drainage under the most adverse conditions. The experiment 
 consisted in the drainage of a piece of land selected as the worst 
 that could be found in a part of the state notorious as having a 
 large area of hard-pan which it was generally considered could not 
 be underdrained “because the soil held water like a jug.” Lines 
 of tile were laid 2 y 2 feet deep and 50 feet apart. The water level 
 
/ 
 
 11 
 
 at a point midway between the lines of tiles was lowered 18 inches, 
 when at the same time the water level in the undrained portion of 
 the field was only 6 inches below the surface. In this case the 
 surface of the ground water had a slope of 1 foot in 25 feet. 
 
 A few other observations seem to confirm the above result for 
 the slope of the surface of saturation in a retentive soil. The exact 
 form of the surface of saturation is not known, but it is known to 
 be a curve slightly convex upward. The inclination varies with the 
 nature of the soil, is most convex near the tile, and is most convex 
 immediately after a rain and gradually thereafter approaches an 
 inclined plane. 
 
 The traveled portion is usually not more than 50 feet wide, and 
 therefore a single line of tile 2 1 /2 to 3 feet below the bottom of the 
 side ditch, if of adequate size, will give nearly perfect drainage; 
 and a second line will not greatly improve it. For example, in 
 Fig. 1, if A represents the first line of tile, the surface of the 
 ground water is represented by the lines ABC. 
 
 Fig. 1. Relative Effect of One Line and of Two Lines of Tile. 
 
 If a second line of tile, D, is laid, the water surface will be 
 A B D, and the second line will drain only the comparatively small 
 portion C B D. The diagram shows that a single line well below 
 the surface is far better than two shallow ones. For example, 
 lowering the tile A 6 inches, lowers the water surface to A'C', 
 which represents better drainage than the line A B D with the two 
 lines of tile. 
 
 It is generally conceded that for agricultural drainage it is 
 sufficient to place the lines of tile 100 feet apart, provided they 
 are of reasonable size and at sufficient depth. A tile will give 
 agricultural drainage 50 feet on either side of it; that is, a tile 
 under only one side ditch will give agricultural drainage of the 
 traveled way. More thorough drainage is required for agricultural 
 
12 
 
 than for road purposes, since when damp most soils will pack, 
 which is harmful to agricultural land but beneficial to a road. 
 
 The above seems to prove that one line of tile, if of proper size 
 and at sufficient depth, will afford sufficient drainage for road pur- 
 poses; but nevertheless it is claimed by competent authorities that 
 two lines are sometimes required. In some localities a stratum of 
 hard-pan near the surface makes it necessary to lay the tile so 
 shallow that two lines are really required; and sometimes the tile 
 is so small or so poorly laid that one line is insufficient. 
 
 In case of doubt as to whether one or two lines of tile are 
 needed, put in one and watch the results. If both sides of the road 
 are equally good, another tile drain is not needed. In making 
 these observations care should be taken not to overlook any of 
 the factors, as, for example, the difference in the effect of the sun 
 upon the south and the north sides of the road, the effect of shade 
 or of seepage water, the transverse slopes of the surface of the 
 road, etc. 
 
 Location of the Tile. Some writers on roads recommend a line 
 of tile under the middle of the traveled portion. A tile under the 
 middle of the road is a little more effective than one at the same 
 level under the side ditch; but the former is considerably more 
 expensive to lay, since it necessitates more digging— whether the 
 tile is laid before or after the road is graded. With the same 
 depth of digging, a tile under the side ditch is more effective than 
 one under the center of the road. Further, if the tile is under the 
 center, there is liability of the settling of the soil in the trench, 
 which will make a depression and probably a mud hole; and if the 
 tile becomes stopped, it is expensive to dig it up, and the doing so 
 interferes with traffic. Finally, if the road is ever graveled or 
 macadamized, the disadvantage of having the tile drain under the 
 center of the road is materially increased. 
 
 Some writers advocate the use of a line of tile near the surface, 
 on each side of the trackway. The object of placing the tile in this 
 position is to secure a rapid drainage of the surface; but very 
 little, if any, water from the surface will ever reach a tile so 
 placed, since the road surface when wet is puddled by the traffic, 
 which prevents the water percolating through the soil. It is certain 
 that in clay or loam the drainage thus obtained is of no practical 
 value. Many farmers have tried to drain their barn-yard by laying 
 
13 
 
 tile near the surface, but always without appreciable effect. The 
 -deeper the tile the better the drainage. 
 
 While a line of tile on one side of the road is usually sufficient, 
 there is often a great difference as to the side on which it should 
 be laid. If one side of the road is higher than the other, the tile 
 should be on the high side to intercept the ground water flowing 
 down the slope under the surface. Sometimes a piece of road is 
 wet because of a spring in the vicinity, or perhaps the road is 
 muddy because of a stratum which brings the water to the road 
 from higher ground; in either case, the source of supply should be 
 tapped with a line of tile instead of trying to improve the road by 
 piling up earth. 
 
 II. Side Ditches. 
 
 The side ditches are to receive the water from the surface of 
 the traveled way, and should carry it rapidly and entirely away 
 from the roadside. They are useful, also, to intercept and carry 
 -off water that would otherwise flow from the side hills upon the 
 road. Ordinarily they need not be deep; but, if possible, should 
 have a broad, flaring side toward the traveled way, to prevent acci- 
 dent if a vehicle should be crowded to the extreme side of the road- 
 way. The outside bank should be flat enough to prevent caving— 
 an important matter which is frequently neglected. 
 
 If the road is* tiled as previously recommended, the side ditch 
 need not be very large; but it should be of such a form as to 
 permit its construction with the “road machine” or scraping 
 grader, or with a drag scraper, instead of requiring to be made by 
 hand. On comparatively level ground, the proper form of side 
 ditch is readily and cheaply made with the usual “road machine.” 
 An example of this form of ditch is shown in Fig. 2. 
 
 Fig. 2. Proper Form of Shallow Side Ditch. 
 
 If a larger and deeper ditch than shown in Fig. 2 is required, 
 it can still be made chiefly and cheaply with the drag-scoop scraper. 
 For an example of a deep ditch of this form, see Fig. 3, page 14. 
 
14 
 
 A deep narrow ditch is expensive to construct, and also expen- 
 sive to maintain, since it is easily obstructed by the caving banks, 
 by weeds, and by floating trash. Fortunately the shallow ditch is 
 easy and cheap to construct and also to maintain. If it is neces- 
 sary to carry water along the side of the road through a rise in 
 the ground, it is much better to lay a line of tile and nearly fill 
 the ditch than to attempt to maintain a narrow deep ditch. A tile 
 is very much more effective per unit of cross section than most 
 open ditches. 
 
 Fig. 3. Proper Form of Deeper Side Ditch. 
 
 The side ditch should have a uniform grade and a free outlet 
 into some stream, so as to carry the water entirely away from the 
 road. No good road can be obtained with side ditches that hold 
 the water until it evaporates. Much ostensible road work is a 
 positive damage for this reason. Piling up the earth in the middle 
 of the road is perhaps in itself well enough, but leaving undrained 
 holes at the side probably more than counterbalances the benefits 
 of the embankment. A road between long artificial ponds is always 
 an inferior one, and is often impassable. It is cheaper and better 
 to make a lower embankment, and to drain thoroughly the holes at 
 the side of the road. Public funds can often be more wisely used 
 in making ditches in adjoining private lands than in making ponds 
 at the roadside in an attempt to improve the road by raising the 
 surface. It is cheaper and better to allow the water to run away 
 from the road than to try to lift the road out of the water. 
 
 When the road is in an excavation, great care should be taken 
 that a ditch is provided on each side to carry away the water so 
 that it shall not run down the middle of the road. Every road 
 should have side ditches, even one that runs straight down the side 
 of a hill. Indeed, the steepest road needs the side ditch most, 
 although it often has none. Frequently the water runs down the 
 middle of the road on a side hill and wears it into gullies, which 
 are a discomfort, and often dangerous, in both wet weather and dry. 
 
 In a slightly rolling country, the side ditch frequently has no 
 outlet, and the water is allowed to accumulate at the foot of the 
 
15 
 
 slope and there remain until it is absorbed by the ground or seeps 
 into a tile drain. Under such conditions, the water seeps away 
 very slowly, since the fine silt washed down from above forms an 
 almost impervious coating which practically prevents any water 
 from percolating through. The difficulty could be remedied by pro- 
 viding an inlet from the open ditch to the tile. This may be a 
 well, walled with plank or masonry without mortar (except near 
 the top) and having a grating in the side or top through which the 
 water may pass. The well should be large enough to allow a man 
 to enter it to clean it, and should extend a foot or more below the 
 bottom of the tile. Earth roads in villages and towns are usually 
 better provided with such inlets than country roads, but both could 
 be materially improved at comparatively small expense by attention 
 to this matter. 
 
 If it can be prevented, no attempt should be made to carry 
 water long distances in side ditches; for large bodies of water are 
 hard to handle, and are liable to become very destructive. Side 
 ditches should discharge frequently into natural water-courses, 
 though to compass this, it may in some cases be necessary to carry 
 the water from the high side to the low side of the road. This is 
 sometimes done by digging a gutter or by building a dam diagonally 
 across the road, but both are very objectionable. A better way is 
 to lay a tile or put in a culvert, the amount of water determining 
 which shall be done. 
 
 It is sometimes necessary to carry water a considerable distance 
 in the side ditches, as, for example, when the road is in excavation. 
 This requires deep ditches, which are undesirable and dangerous; 
 and if the grade is considerable, the ditches wash rapidly. In 
 such cases, it is wise to lay in a line of tile under the side ditch, 
 and turn the water from the surface ditch into the tile at intervals. 
 This can be accomplished readily by inserting in the line of porous 
 tile a Y section of vitrified sewer pipe, with the short arm opening 
 up hill. Of course, the short arm, i. e., the vertical arm, need not 
 be as large as the body. If necessary, two or three lengths of 
 porous tile- may be added at the upper end of the Y to make con- 
 nection with the bottom of the open ditch. Earth, sods, or stones 
 can be piled around the upper end of the tile to make a dam and 
 to hold the tile in place. 
 
16 
 
 As a rule, side ditches will not have too much fall, but some- 
 times a ditch straight down a hill will have so much fall as to 
 wash rapidly, in which case it is an advantage to put in an ob- 
 struction of stone or brush. In extreme cases the bottom of the 
 ditch is paved with stones. 
 
 m. Surface Drainage. 
 
 The surface drainage of a road is provided for by making the 
 traveled way crowning and keeping it smooth. The making of the 
 road crowning in the beginning is a matter of construction, and 
 the keeping of the surface smooth is a question of maintenance. 
 It should be remembered that water upon the surface of the road 
 can not be carried away by the underdrains until after it has pene- 
 trated and softened the road surface. 
 
 Constructing the Crown. The slope from the center to the side 
 should be enough to carry the water freely and quickly to the side 
 ditch; and if the surface is kept free from ruts and holes, less 
 crown will suffice than if no attention is given to keeping the sur- 
 face smooth. If there is not enough crown, the water can not 
 easily reach the side ditches; and hence the road soon becomes 
 water soaked. 
 
 On the other hand, the crown may be too great. If the side 
 slopes are so steep that traffic keeps continually in the middle, the 
 road will be worn hollow and retain the water instead of shedding it 
 promptly to the side ditches. With the ordinary method of caring 
 for earth roads, more water stands on a very convex road than on 
 a flatter one. If the crown is too great, it is difficult for vehicles 
 to turn out in passing each other. Again, if the earth is piled too 
 high in the middle, the side slopes will be washed into the side 
 ditches, which not only damages the road but also fills up the 
 ditches. Further, if the side slopes are steep, the top of the wheel 
 will be farther from the center of the road than the bottom, and 
 the mud picked up by the bottom of the wheel will be carried to 
 the top of the wheel and then dropped farther from the center of 
 the road than it was before, each vehicle acting like a plow and 
 moving the earth from the center toward the side of the road. 
 
 The slope from the center to the side should be at least half an 
 inch to a foot, or 1 foot in 24 feet; and it should not be more 
 than 1 inch to a foot, or 1 foot in 12 feet. If the surface is well 
 
17 
 
 cared for, the former is better than the latter; but in no case is it 
 wise to exceed the latter slope. For a diagram showing a cross 
 section of a road having the first named slope, see Fig. 2, page 13, 
 and for the cross section of a road having the second slope, see Fig. 3, 
 page 14 ; and for a road on an embankment, see Fig. 4. 
 
 Fig. 4. Proper Crown for Road on Embankment. 
 
 The crown should be greater on steep grades than on the more 
 level portions, since on the grade the line of steepest descent is not 
 perpendicular to the length of the road, and consequently the 
 water in getting from the center of the road to the side ditches 
 travels obliquely down the road. If the water once commences to 
 run down the center of the roadway on a steep grade, the wheel 
 tracks are quickly deepened, stones are loosened or uncovered, and 
 the road becomes rough and even dangerous. Under these circum- 
 stances, it is necessary to construct catch-waters, “ water-breaks / 9 
 “hummocks,” or “thank-you-marms” at intervals to catch the 
 water which runs longitudinally down the road, and convey it to 
 the side ditches, thereby preventing the formation of gullies in the 
 road surface. These catch-waters may be either broad shallow 
 ditches or low flat ridges constructed across the road; and they 
 may slope toward one or both ditches. In the former case, they 
 should cross the road diagonally in a straight line; and in the 
 latter case, in plan they should be a broad angle with the apex at 
 the center of the road pointing up hill. There is little or no differ- 
 ence between the merits of the ditch and the ridge, unless the 
 bottom of the former is paved with gravel, broken stone, or cob- 
 bles. The ridges are more common, but usually are so narrow and 
 so high as to form a serious obstruction to traffic. However, 
 neither the ditches nor the ridges should be used except on steep 
 grades where really necessary, since either form is at best an 
 obstruction to travel. The angle that the catch-waters shall have 
 with the axis of the road should be governed by the steepness of 
 the grade— the steeper the grade the more nearly should the catch- 
 waters run down the road. They should have a considerable 
 
18 
 
 breadth so that wheels may easily ascend them and horses will not 
 stumble over them. 
 
 Catch-waters should also be constructed in a depression where 
 an ascending and a descending grade meet, in order that they may 
 collect the water that runs down the traveled way and convey it 
 into the side ditches. These catch-waters should run square across 
 the road, and should be quite shallow ditches, the bottom of which 
 is hardened with gravel, broken stone, or cobbles. 
 
 Some writers recommend that a surface of the road on the face 
 of hillsides should consist of a single slope inclining inwards. This 
 form of surface is advisable on sharp curves, but is of doubtful 
 propriety elsewhere. The only advantage of this form is that the 
 water from the road is prevented from flowing down the outer face 
 of the embankment; but the amount of rain water falling upon one 
 half of the road can not have a very serious effect upon the side 
 of the embankment. With a roadway raised in the center and the 
 water draining off to either side, the drainage will be more effectual 
 and speedy than if the drainage of the outer half must pass over 
 the inner half. If the surface is formed of one plane, the lower 
 half of it will receive the greater share of the travel; and as it 
 will be more poorly drained, it is nearly certain to wear hollow. 
 This will interfere with the surface drainage; and consequently 
 a road with this section will require excessive attention to keep it 
 in good condition. 
 
 Whatever the form of the road surface, if the hillside is steep 
 there should be a catch-water above the road to prevent the water 
 from the hillside above from flowing down on the road. It should 
 be, say, 6 feet back from the excavation, and should have a width 
 and depth according to the amount of water to be intercepted. 
 
 Maintaining the Crown. Proper maintenance is as important 
 as good construction. A distinction should be made between main- 
 tenance and repairing. The former keeps the road always in good 
 condition; the latter makes it so only occasionally. If the road is 
 not properly maintained, it deteriorates in a geometrical ratio— 
 a small depression fills with water and soon becomes a mud hole 
 which traffic makes deeper and deeper, or an obstructed side ditch 
 forces the water to run down the center of the road and gullies 
 
19 
 
 •out the surface. A defect which could be remedied in the begin- 
 ning with a shovelful of earth or a minute’s time, if neglected may 
 require a wagon load of earth or an hour’s time, besides being in 
 the meantime an annoyance or a danger to traffic. The better the 
 state in which the road is kept, the less are the injuries to it by 
 •ordinary traffic and the weather. 
 
 Water is the natural enemy of good earth roads. The chief ob- 
 ject of maintenance should be to keep the surface smooth and 
 properly crowned so that rain water will be shed promptly into the 
 side ditches. These should be kept open so that the water may be 
 carried entirely away from the road. 
 
 Smoothing the Surface. The most important work in maintain- 
 ing an earth road is to keep the surface smooth so that the rain 
 water will flow quickly in to the side ditches. If the surface of 
 the roadway is properly formed and kept smooch, the water will 
 be shed into the side ditches and do comparatively little harm; 
 but if it remains upon the surface, it will be absorbed and convert 
 the road into mud. If all ruts, depressions, and mud holes are not 
 filled as soon as they appear, they will retain the water upon the 
 surface, to be removed only by gradually soaking into the road-bed 
 and by slowly evaporating; and each passing wheel or hoof will 
 help to destroy the road. 
 
 There are several machines or devices which are very effective 
 in filling ruts and depressions, and in keeping the surface smooth. 
 The different tools are best under different conditions. 
 
 Harrow. In the winter there frequently come times when the 
 road is full of holes and ruts, while the surface soil is dry and 
 mellow. This condition occurs most frequently when the ground 
 below the surface is frozen. If at this time a harrow is run over 
 the road, it will fill up the ruts and holes and leave the surface 
 comparatively smooth. This improves the road for present travel, 
 and gives a smooth surface which will greatly decrease the de- 
 terioration of the road by subsequent rains. The ordinary adjust- 
 able farm harrow should be used, and the teeth should be set to 
 slope well back. The labor required is not great, since a 12-foot 
 harrow can be used, and then a single round is sufficient. 
 
20 
 
 Often there are only a few hours in the middle of the day when 
 the frost is out of the ground sufficiently to permit this work to be 
 done, and therefore it is best for each farmer to harrow the road 
 adjoining his own land. The work comes at a season of the year 
 when the farmer’s time is usually not very valuable, and hence the 
 expense is small. This method of treating earth roads has proved 
 very beneficial both in securing good roads and in preserving them. 
 
 In the summer, when the roads get roughed up, they can be 
 materially improved at small expense by running over them with a 
 harrow having the teeth down quite flat. If the roads are a little 
 muddy, this treatment will make them dry faster and also make 
 them much more pleasant to use after they have dried. 
 
 Railroad Rail. In the early spring, just after the frost goes out 
 of the ground, earth roads are usually full of deep ruts. The har- 
 row is not suitable for the work now required. The object is 
 simply to cut off the ridges and fill up the ruts, and thus 11 break 
 the way” for travel. It is well to break the road early in the 
 season, both to accommodate immediate travel and to hasten the 
 coming of a better condition of the road. It is much more econ- 
 omical to make the road smooth with a railroad rail or its equiva- 
 lent than to wear it down by travel. 
 
 A railroad rail 14 to 16 feet long drawn by two two-horse teams 
 has been used with great success in breaking down the ridges and 
 filling up the ruts. The team is hitched to an eye fastened through 
 the web 2 or 3 feet from the end of the rail. The edge of the base 
 of the rail serves as a cutting edge. A 7-inch steel I-beam is 
 equally good. 
 
 When the ground is mellow and loose after freezing and thawing, 
 the steel rail will smooth the road nearly as satisfactorily as the 
 “road machine,” or scraping grader, as it is more properly called, 
 and much more rapidly, since it cuts a wider swath and since the 
 draft is so light that the teams walk right along. One round trip 
 is usually sufficient for any road. The time when the work is 
 most advantageously done is comparatively limited; and therefore 
 one rail should not be expected to cover too much road. The cost 
 is so small that one can be provided for each few miles of road — 
 the number depending upon the climate and the nature of the soil. 
 If roads are treated 'in this way, they will not get so rough; and 
 hence will require less work later with the heavy road machine. 
 
21 
 
 Light Scraper. A heavy stick of timber, say, 6 x 12 inches, faced 
 on one side with a steel plate, and drawn bj a team, is very ef- 
 fective in smoothing the way for travel. To the top face of the 
 timber should be fastened a frame by which to hitch the team. 
 This frame should be in the form of a capital A with one leg a 
 little shorter than the other, to cause the cutting edge to stand 
 obliquely to the line of draft. The blade should be about 14 inch 
 thick, 4 inches wide, and as long as the timber, say 6 or 7 feet. 
 
 There are many i 1 road machines ” on the market, all of which 
 are most excellent for certain kinds of work, but most of which are 
 too heavy for the conditions just described. Most of the machines 
 are mounted upon four wheels, and of themselves are a considerable 
 load over roads which are only a succession of ridges, ruts, and 
 mud holes; and are heavier and more cumbersome than is neces- 
 sary for the work now under consideration. 
 
 Split-Log Drag. Fig 5 shows a form of road drag first made by 
 Mr. D. Ward King, of Missouri. The main pieces are the two 
 halves of a log 10 or 12 inches in diameter and 7 to 9 feet long. 
 
 The log should be some light wood, as oak is too heavy. The cross 
 sticks should be about 30 inches long. The ring or hook to which 
 the double-trees are attached should be about 2 or 2l/ 2 feet in front 
 of the drag. The two pieces of the chain should have such lengths 
 that the log will stand at an angle of about 45° with the direction 
 the team travels. The lower edge of the front slab should prefer- 
 ably be protected by a steel plate *4 inch thick and. 3 or 4 inches 
 
22 
 
 wide. A wide plank should be laid upon the connecting sticks, upon 
 which the driver may stand. 
 
 A drag similiar to that shown in Fig. 5 may be made of a 2^inch 
 by 10-inch or a 3-inch by 12-inch plank instead of the two halves 
 of a split log. Mr. King deserves credit for the intelligence and 
 persistency with which he has advocated the use of the drag in 
 keeping smooth the surface of an earth road. If the surface of 
 the road is kept smooth, the rain water is speedily drained into 
 the side ditches and besides the road is always pleasant to drive 
 upon.