REPORTS ON ADDITIONAL WATER SUPPLY FOR THE CITY OF HARTFORD. HARTFORD : / PRESS OF CASE, LOCKWOOD AND COMPANY. 1862. gm, fO* (S / ** k a , U (J V Li i ^ Ut5* REPORT. Office Water Commissioners, ) Hartford, March 8th, 1862. ) To the Honorable the Mayor and Court of Common Coun- cil of the City of Hartford : Gentlemen, — At a meeting of your honorable body, held May 27th, 1861, the following vote was passed by concur- rent action : Voted , “ That the reports and papers relating to an addi- tional supply of water for the city, be referred to the Board of Water Commissioners, with power to employ such assist- ance as may be needed to re-examine and report anew on the various projects for furnishing the city with an addi- tional supply of water.” This Board, fully appreciating the importance of a sub- ject so vital to the interests of the city as its water supply, respectfully beg leave to report, that in accordance with the foregoing vote, and with a view to elicit information of a reliable character, they employed Prof. B. Silliman, Jr., Analytical Chemist, to examine the waters of Trout Brook, at West Hartford, and report as to their chemical and physical properties, and the adequacy of the supply from that source. His very able report, in detail, we herewith submit and recommend the same to your careful consider- ation. The Board also employed McRee Swift, Esq., civil engi- 4 neer, whose large experience in the construction of water- works has eminently qualified him for the duties required. He was instructed to examine the whole subject of our present and prospective wants, relative to a water supply, and report on what, in his opinion, would be the most reliable, economical and best plan for obtaining such addi- tional supply. This service Mr. Swift has performed, and his able report is herewith submitted to your honorable body. It will be observed by reference to this report that Mr. Swift estimates on two plans, one by pumping, and one by gravitation, and recommends the latter for adoption. By reference to Prof. Silliman’s report, it will be found that the water from the proposed source at West Hartford, is of a very pure quality, and that no fears need be enter- tained as to any unfavorable effect of storing the same in reservoirs. In regard to our present condition, relative to the ef- fectual head upon which the city is now dependent for its water supply, actual experiment has verified the fact, that at present rate of consumption, the Ordinary draught during the day, upon the distributing pipes, reduces the effectual head about fourteen feet. The whole loss of the effectual head may be thus stated : Average depression below full head in reservoir, 2 feet. Loss by distributing draft as above, . 14 “ Height of faucets on first floors above road bed, 8 “ Total loss or difference between apparent and effective head, ... 24 feet. The following statement shows the actual and effective head as it exists at various points in the city : Effective . , , , , head on Actual head fl rs t floor with a full as it ordi _ reservoir. narily ex- ists. At road bed on Main street near Trumbull street, 52 feet. 28 feet. u “ in front of State House, 66 “ 42 u it “ in front of South Church, 73 “ 49 u u “ at Canton street, 44 “ 20 5 At road bed on Main st. at Arsenal Gate, 41 feet. 17 feet. « ~ — “ “ Suffield street, 38 u 14 kt tt “ Washington st., cor. Buckingham, 43 u 19 tt tt “ “ cor. Jefferson st., 36 a 12 a it “ “ Hydrant in front of Retreat Gate, 12 “ 0 it At road bed on Washington st. at New Britain and ♦Webster st. 16 u 0 u At road bed on New Britain av. in front of J. S ey- mour’s road, 12 u 0 “ At road bed on New Britain av. in front of H. Seymour’s late residence, 5 a 0 n At road bed on Webster st. in front of Edwin Merritt’s house, 22 it 0 tt At road bed on Webster st. at junction with Ma- pie avenue, 39 u 15 tt At road bed on Vernon st. cor. of Washington, 18 a 0 u tt “ M at road in front of John Allen’s house, 15 it 0 a At road bed on Baker st. at hydrant corner of Wolcott st., 49 tt 25 a At road bed on Baker st. at cor. Linden st., 42 tt 18 tt tt “ “ Affleck st., 34 a 10 tt tt “ “ Putnam st., 22 u 0 u it “ “ Zion st., 20 tt 0 n tt “ Park street, u 27 tt 3 tt tt “ “ Affleck st., 45 tt 21 u tt “ Retreat av. at Retreat Gate, 50 u 26 tt tt u Capen st., cor. of Clark st., 30 tt 6 n it Clark st., in front of Peckham’s house, .... 32 tt 8 a At road bed on Clark st. at Westland st., 27 tt 3 a a “ Albany av. at Center st., 65 tt 41 u tt u “ Kenyon’s House, 63 “ 39 a tt “ Maple av. at Gate at the Retreat Grounds, .... 46 it 22 tt At road bed on Maple av. at junction of Webster, 39 tt 15 u 6 The annual increase of the consumption of water, and the corresponding increase of engine duty, is shown by the following table : Running o 02 1 £ I 9 g-g'S? T3 J.9 bS • time. to • o 9 « ► T? CD _C3 •! *§ g £ Year. Hours. Min. H.S * rfJ SCO |1 g Total poi of Coal consume Gallons c Water d< ed into tl Reservoii © £3 © CG • ® w rt a s ► s Z g < © .9 <2 o Av. No. < Gals, com each day the year. # • £ ® ^ © O «l £ S- > d © $ •<©.S 10 months for 1856. 12 months 1,291 690,228 232,944 104,914,656 450 345,114 for 1857. 12 months 2,169 1,248,762 376,900 190,456,203 505 521,797 176,683 for 1858. 12 months 2,718 50 1,589,211 489,024 242,354,674 495 661,245 139,448 for 1859. 12 months 3,205 35 1,879,663 582,375 286,648,604 492 785,338 124,093 for 1860. 12 months 3.577 11 2,147,004 683,200 327,417,801 479 897,035 111,697 for 1861. 4,429 30 2,630,035 777,928 401,080.335 515 1,098,850 201.825 The imperative necessity of providing for an additional supply of water from some source, and at an additional elevation of reservoir head, sufficient to meet the growing demands of the higher portions of our city ; and the dan- ger of accidents to the present machinery, upon which our supply of this indispensable element of existence so entire- ly depends, have long protruded themselves with such painful earnestness upon the Board of Water Commission- ers, that they have frequently solicited the attention of the council to the subject. The opinion which they have heretofore, and uniformly expressed, in favor of meeting these additional wants, by a supply by gravitation from Trout Brook, so called, in West Hartford, was not a mere theoretical or speculative opinion, loosely formed, but was the result of patient and careful investigation of the whole subject — and neither a single member of the present, nor any past Board, who has participated in those investigations, has ever come to any different result, or has hesitated in giving this the preference over every other plan proposed. The Board therefore, in cordially indorsing, as they do, the mode of supply recommended in the accompanying reports, from gentlemen of great professional skill and science, and eminent as adepts on such matters, only reit- erate their former convictions upon this subject. Respectfully submitted, HIRAM BISSELL, E. D. TIFFANY, SETH E. MARSH, N. H. MORGAN, D. CRARY, PROF. SILLIMAN’S REPORT ON THE WATER SUPPLY HERTFORD. HARTFORD: PRESS OF CASE, LOCKWOOD AND COMPANY. 1861 . Digitized by the Internet Archive in 2017 with funding from University of Illinois Urbana-Champaign Alternates https://archive.org/details/reportsonadditioOOhart CONTENTS. Page. Address to the Commissioners, .... 5 Sources of Auxiliary Supply, .... 5 Flow of Water, ..... 6 Estimate of Flow from Rain Fall, .... 7 Purity of Waters — Physical Properties — A. Color, . 9 B. Transparency — C. Taste — D. Smell, . . 10 Chemical Examination of the Waters, . . .11 Comparative Purity and Hardness of several Waters, . 12 Comparison of these results with the Analysis of several Well Waters from Hartford, . . . .14 Comparative Hardness of Waters, . . . 15 Action of the Waters on Lead, . . . .17 Acid or Alkaline Condition of the Waters, . . 18 The Probable Effects of Storing the Waters of Trout Brook, 19 Cause of Annoyance at New Britain, . . . 19 Good Success of Storing at Brooklyn, . . .20 What Precautions should be taken to Secure the Best Possi- ble Quality of Water for a City Supply, . . 21 Filtration — Difference between Spring and Rain Water — Aeration, . . . . . .22 Structure of Filters, . . . . • 23 REPORT. To the Board of Water Commissioners of the City of Hartford: Gentlemen : At your request I have examined the sources of water supply in West Hartford, which are under consideration as an auxiliary source for the city of Hartford. The samples collected by me, both from the stream in question and from the Connecticut, have been chemically examined, and I now present for your consideration the following REPORT. SOURCES. The source from which it is proposed to draw the addi- tional water supply is the valley of a small rivulet called Trout Brook, in West Hartford. The region drained by this stream and its branches is a part of the general water shed of the Connecticut. The soil is derived from the spoils of the red shales and trap rocks forming the Talcott mountain range and its subordinate hills. The red sand- stone of this part of the valley is a soft, rather fine grained shale, not particularly argillaceous or calcareous. The gravel and loose materials of the surface are clean and fitted to form embankments. A part of the valley of Trout Brook, especially along the bottoms of the streams, is now covered by a dense undergrowth of trees and shrubs, giving shelter to aquatic « 1 6 and bog frequenting plants, whose roots and decaying leaves or stems color the water somewhat with vegetable matter, as is the case almost universally in streams of soft water. The clearing away of the causes of this coloration will diminish or entirely remove these effects. At the margin of what may be called the swampy bot- toms of this stream, is found in several places and for a considerable distance, the out crop of a soft shale, on the edges of which numerous springs of clear, sparkling water are found. These now lose themselves, for the most part, in wet, boggy land ; but wherever, for farm purposes, an exca- vation has been made on this line, beautiful perennial springs are produced. The water from these sources was separately examined.* It is what is commonly called “ pure spring water,” and forms a valuable item in the supply to be stored. The main stream divides into two branches not far from where it is proposed to construct the dam, — the left branch coming from the north, while the right branch flows down from the western hills. The ground on both these streams is favorable for storing water in reservoirs, sup- plemental to the larger one on the main stream. The chemical examinations, presently to be detailed, show .that in the qualities required in a source of supply for a large town, the waters of this stream are all that can be desired. FLOW OF WATER. On the 11th of June, I estimated the flow of this stream as about six millions of gallons for the twenty-four hours. On the 16th of July, after an almost uninterrupted drouth of six weeks, this flow had diminished ten fold, or to about six hundred thousand gallons. I leave it for your Engineer to show, from frequent and long continued observa- tions, what he considers the average flow for the whole year. * See No. 3 of the Analyses, p. 1 1 » 7 I would simply remark in passing, that experience shows in similar cases, when a brook flows over a clean pebbly bot- tom, that the attempt to gauge it by a board dam always gives a less amount than the actual flow, from the impossi- bility of preventing leakage through the porous bottom of the stream itself ; so that the results obtained by ponding or storing are liable to exceed the calculations based on gauging. ESTIMATE OF THE FLOW FROM THE RAIN FALL. A little calculation from well established data will show what the storage capacity of the stream is, and you can determine from other sources how nearly this result cor- responds with the truth. I estimate that Trout Brook represents, at the point where the main reservoir is to be established, the drainage of not less than ten square miles of surface. As the springs and streams of a limited district like this represent in their aggregate only the annual rain fall of the district — less the amounts lost in evaporation and soakage — it fol- lows that we have in a given case the elements of a calcula- tion, which will show pretty closely the available water- producing capacity of the district. From a long series of Meteorological Observations made for many years at New Haven, by the Connecticut Academy of Arts and Sciences, it appears that the average annual rain-fall of this place is about forty-four inches. It can not be much different in the vicinity of Hartford. Hydraulic engineers agree, I believe, in estimating the available amount of water in a river valley as equal to about half the aggregate rain-fall. It is sometimes stated as low as four-tenths of this quantity. Let us employ the smaller number in this estimate. On each superficial acre of ground are 43,560 square feet, on which a rain-fall of forty-four inches annually pre- cipitafes an aggregate of very nearly 160,000 cubic feet of 8 water, (159,480 exactly.) This is equal to 10,000,000 pounds, a cubic foot of water weighing 62.5 pounds. As the imperial gallon holds ten pounds of water, this weight corresponds to 1,000,000 gallons. Assuming that four- tenths of this quantity may be stored, we have an available storage per acre of 400,000 gallons. Each square mile (640 acres) of water shed will yield therefore 256,000,000 of gallons annually. If then there are ten square miles of area on the water shed of the Trout Brook and its affluents, we have the grand aggregate net accumulation available for city supply, equal to 2,560,000,000 gallons annually. As by the last Annual Report of your Board the daily average consumption in Hartford did not exceed 1,000,000 of gallons, it would seem safe to look to Trout Brook as a reliable source of auxiliary supply, so far as to the quantity of water, proper provision being made for storage. It will be remembered that this estimate does not show the total aggregate rain-fall, but only the available quantity left after all losses from evaporation, soakage, &c., have been allowed for in the most liberal manner. As the basis of this calculation is beyond question reliable, (i. e. the average annual rain-fall,) it is plain you can afford to grant all the deductions from this estimate which the most incred- ulous may be disposed to make and still retain an available aggregate far in excess of any present or prospective demand of your city. As the results just given may startle those who have not considered the almost unmeasured bounty of nature in her water supply, it may be well to recall the fact that the estimated flow of Trout Brook on the 11th of June, at 6,000,000 gallons daily, corresponds to an aggregate flow of nearly 2,200,000,000 of gallons yearly. If the flow had been 7,000,000 daily in place of 6,000,000, the aggregate would have been annually - - - 2,555,000,000 while the calculation requires - - 2,560,000,000 This singular coincidence goes far to show that the flow of 9 F Trout Brook on the 11th of June was not far from its average daily flow for the whole year. Since making this calculation, I learn from Mr. Bissell, without communicating to him my results, that he has fixed the daily average flow of the stream for the whole year at about seven millions of gallons. We may here rest the inquiry as to the adequacy of the supply from this source, believing it to be beyond all dispute, abundant. Let us now inquire, 1st. As to the purity of the water from Trout Brook, comparing it with that now in use in Hartford and in other places. 2d. Whether there exist any causes which may unfavor- ably affect the continued purity of the water when stored in reservoirs, considering in this connection analogous cases of storage. 3d. Precautions desirable to be taken to secure the best possible quality of water for a city. 1st. purity of the water.— physical properties. The following results have been attained from samples of the waters described, taken on the 11th of June. They were collected in clean basket bottles, and were suffered to repose for some days before the trials were made. No. 1. Water drawn from the main stream of Trout Brook, near where the proposed dam is to be located. No. 2. Was from the north fork of the main stream. No. 3. Was from one of the springs on the Shale near the margin of the wet land. No. 4. Was from the Connecticut River, drawn from the rising main at the Pump House of the City Works. A. COLOR. Comparing No. 1, 2 and 4, in colorless glasses of equal size and form, looking down through the water upon a pure white surface, all lateral reflection being cut off, all appeared brownish. This color was stronger in No. 4 2 10 than in the others, least in No. 2, and in No. 1 intermediate between the two others. No. 3 was absolutely colorless as compared with pure distilled water. B. TRANSPARENCY. After agitating the water in the demijohns, the following observations were made on comparative transparency. No. 1. Numerous minute flocks were seen of apparently very light substance, slowly settling to the bottom of the vessel and slightly disturbing the transparency of the water. After twenty-four hours rest all these particles were not completely subsided. No. 2. This was quite bright, transparency not disturbed by agitation, almost no sediment or floating particles. No. 3. Completely bright and undisturbed, no floating particles or sediment. No. 4. Much disturbed by floating particles, apparently of organic substance, settling very slowly to the bottom in brownish pellets. After twenty-four hours of repose this sediment had not completely subsided. C. TASTE. No. 1. This had a decided taste of vegetable matter, similar to the familiar taste of Croton water when not iced, but not as strong. No. 2 and 4. Both these have less taste than No. 1, but as between themselves no difference could be detected. No. 3 was quite destitute of taste, no trace of vegetable flavor, but the sprightly character of the best spring water. D. SMELL. No. 1. Has a fresh smell, such as belongs to all soft brook water. No. 2. Has the same odor in a much less degree. No. 3. Is destitute of all odor. • No. 4. Is slightly odorous in a less degree than No. 1 and 2, but the odor of the same quality. 11 From these observations I infer that the water of the main stream in Trout Brook is at least as free from color, smell and taste as Croton water. That the water of the north branch is superior in all respects to the same stand- ard. That Trout Brook has less suspended matter in it than is found in the waters of Connecticut River at an average stage, and that the color and other physical prop- erties noted are derived chiefly from the westerly branch of the main stream, since the north branch is much freer from these peculiarities than the main stream itself. The cause of this difference is obvious on an inspection of the ground over which the two streams flow, that on the western stream having more decomposing vegetable matter, all of which should be removed before flowing the ground. CHEMICAL EXAMINATION OF THE WATERS. No. 1. One gallon* of this water contains 3.268 grains of solid matter consisting of Organic matter, 1.634 grains, Inorganic matter, silica, .642 Lime, magnesia, alkalies, chlorine, sulphuric and carbonic acids, .992 — 1.634 3.268 No. 2. One gallon of this water contains 2.043 grains of solid matter consisting of Organic matter, 1.226 grains. Inorganic matter — silica, .543 Lime, magnesia, alkalies, chlorine, sulphuric and carbonic acid, .274 — .817 2.043 No. 3. One gallon of this water contains 3.572 grains of solid matter, consisting of # The American standard gallon of 58,372 Grains. 12 Organic matter, .934 grains. Inorganic matter — silica, .502 Lime, magnesia, alkalies, chlorine, nitric acid and carbonic acid, 2.136 — 2.638 3.572 contains 2.568 grains 1.051 .210 1.307—1.517 2.568 In these determinations all suspended matter was re- moved by filtration. The first thing which strikes the attention on examining these results is the remarkable purity of all these waters. This will be rendered more conspicuous by observing the annexed table giving the results of the total solid contents, &c., of some other metropolitan water supplies. Table. Comparative purity and hardness of several waters used for Metropolitan supply. No. 4. One gallon of this water of solid matter consisting of Organic matter, Inorganic matter — silica, Lime, magnesia, alkalies, sul- phuric and carbonic acids, Waters. A. B. c. D. E. F- G. H. Total solid contents one Imp. gallon, 19.50 21.72 12.71 6.59 4.04 3.07 3.91 52.28 “ organic matter, 2.79 3.07 4.73 1.40 1.39 1.26 1.95 “ inorganic matter, 16.71 18.65 7.98 5.19 2.65 1.81 1.95 Carbonate of lime, 7.82 10.90 2.52 2. .29 .01 .017 16.20 Degree of hardness, 14. °9 14° 1°.64 1°.19 10°.55| A. New River, London, B. River Thames, “ C. Croton River, New York, T). Fairmount, Philadelphia, E. Cochituate, Boston, F. Connecticut, Hartford, G. Trout Brook, West Hartford, H. Well, N. W. corner State House yard. The above analyses are calculated for the Imperial gallon, containing 70,000 grains of distilled water. by Dr. Graham and others. ii ii ii “ Author, 1845. u u a a a << “ “ June, 1861. 13 An inspection of this table will show that the waters used and proposed to be used for the supply of the city of Hartford are of almost unequalled purity and softness. I have selected two of the London waters as the best example of a moderately hard river water from a calcareous district. The London waters are remarkable for their brilliancy , a quality due to.the lime which combines with and throws down the vegetable matter. It has been shown, by an extended chemical research, that the maximum of organic matter is found in natural waters at mid-summer, is at a minimum in winter after freezing, and is diminished by rains. We may therefore expect the water from Trout Brook to give better results in this particular by storing than we have obtained in this examination ; although it is difficult to know why anything better should be desired. ‘ The exact apportionment of the very minute quantities of the several mineral constituents in the Hartford waters can be of no practical importance. The quantities avail- able are too small for the most satisfactory results. An- nexed are, however, the ratios obtained for the principal constituents in No. 1, calculated for one standard gallon, which contains 58,372 grains, as follows: — Alkalies, (potasli and soda,) .238 Magnesia, .141 Lime, .617 Silica, .473 Chlorine, .070 Sulphuric acid, .092 Total inorganic matter, 1.626 “ organic u 1.634 3.260 “ water and air in solution, 58,368.740 u grains in one gallon, 58,372.000 14 COMPARISON OF THESE RESULTS WITH THE ANALYSES OF SEVERAL WELL WATERS FROM HARTFORD. Several years ago, about the time the public mind began to direct itself to the subject of water supply in Hartford, several analyses were made in my laboratory by Mr. B. W. Bull, of the waters of some pyiblic and private wells in your city. I believe it will be interesting to cite these analyses in this connection, especially as some of them are used as terms of comparison for the hardness test under the next hea # d. The waters analyzed were taken in 184T from the follow- ing wells : No. 1 was from a well in the North-west corner of the State House Yard. No. 2 was from the well of H. Seymour (formerly) 16 (now No. 43) Main street. No. 3 was from the well on the grounds of the American Asylum. No. 4 was from Lane’s Coffee House, North Main street. No. 5 was from the New England House, Front street. The results of the analyses of these waters are given in the following Tables. Table I. gives the specific weights and the amount of solid contents left on evaporation in one American standard gallon of 58,372 grains at 60° F. Table I. No. 1. No. 2. No. 3. No. 4. No. 5. Specific gravity, (pure ) water being 1 .00000, ) £ Grains of solid matter ) in one gallon, ) 1.00081 41.479 1.00044 32.157 1.00010 19.334 1.00078 37.102 1.00106 69.046 Table II. gives the amounts of the several constituents found by analysis : 15 Table II. Constituents of one gallon in grains , as found by analysis. It No. 1. No. 2. No. 3. No. 4. No. 5. Chlorine, 12.765 3.563 2.407 3.517 21.557 Sulphuric Acid, . 2.296 2.114 1.028 2.710 3.061 Carbonic Acid, . 6.449 3.429 .561 3.826 4.533 Lime, 12.192 7.671 7.075 8.103 10.358 Magnesia, . 1.168 1.116 .555 4.621 5.293 Alumina and Iron, .204 2.267 .261 traces. Alumina, .817 Soda, 7.437 6.362 6.893 13.764 23.718 Silica, 1.052 3.474 .817 .261 .526 Ammonia, . Nitric Acid, j traces. traces. • • 1 43.563 29.996 20.153 37.063 69.046 Comment is needless to show the great inferiority of the old well waters as compared with the improved sources now in use or at command.* COMPARATIVE HARDNESS OF WATERS. The quality of hardness in waters is one well understood in the common experience of life. This quality is owing chiefly to the presence of salts of lime. Water is called hard because it forms with soap a harsh curd, which inter- feres with the process of washing. This curd is an insolu- ble lime soap, and its production is at the cost of a quantity of soap proportioned to the hardness of the water. In wash- ing with a hard water, soap enough must be used to destroy the lime salt, before any useful effect is obtained from it. When magnesia is present in any considerable degree, it greatly modifies the eifect of the lime. A solution of soap in diluted alcohol forms a very con- venient test for the hardness of waters ; and by using a solution of lime of known strength, as a term of compari- son, a scale of degrees of comparative hardness may be * See Mr. Bull’s paper in the American Journal of Science, [2] IV., 385. 16 obtained. The scale of Dr. Clark, of England, is that most in use. On this scale each degree of hardness represents one grain of carbonate of lime (or its equivalent) in one imperial gallon or 70,000 grains of water. Tested in this way your waters give the following results : SOURCE OF WATER. HARDNESS. West Hartford, June 11, . . . 1°.19 46 44 Spring, (No. 3,) . . 1°.61 Connecticut River, 1°.64 Well at N.W. corner State House Yard, Aug. 28, 10°.55 44 on H. Seymour’s residence, Main street, 13°.44 44 44 Grounds of American Asylum, 8°. 39 44 at New England Hotel, Front street, 19°. 22 I do not offer the results obtained on the hardness of the well waters above given, in order to compare them with the analyses of Mr. Bull in 1847. * Many circumstances may have varied the composition of these waters, and to institute a comparison, a new set of analyses would be required on the waters as they now are. The object in view did not seem to require this additional labor, since nobody now proposes to resume the use of these wells. It is, however, not uninstructive to note the economical advant- ages of using soft water, such as you now enjoy, as com- pared with the effects of the well water formerly in use. The effect of hardness in waters is such that each grain of carbonate of lime (or its equivalent salt) in a gallon of water, destroys ten grains of soap. Assuming each degree of hardness as the equivalent of one grain of lime, and taking the average of hardness in the above well waters at 13°, it follows that the hardness in 100 gallons of such water would occasion the loss of about thirty ounces of soap, before any useful effect is produced. The lime in the same quantity of Trout Brook water, as it was June 11, „ would destroy only about 120 grains of soap, less than 108th part as much as the water from the old wells. 17 The same is true in an almost equal degree for the waters of Connecticut river. You enjoy, therefore, almost une- qualled softness of water for metropolitan supply. The advantages of soft water in the better preparation of food are as important as those found in washing, bathing and manufacturing uses. The only cause *of anxiety to be felt from the use of soft water is in the fact that some soft waters act injuriously on lead. This cause of anxiety, happily, is shown by the exper- iments made with lead in connection with your waters to be without any foundation in fact. The results alluded to are next in order. ACTION OF THE WATERS ON LEAD. To test this very important point, equal sized plates of bright lead were placed in bottles, each containing a speci- men of one of the waters, while a similar slip was exposed in the same manner in distilled water. In Nos. 1, 2 and 4 there was observed, after twenty-four hours exposure, a discoloration of the lead from the precipitation of a brown- ish compound upon the surface of the lead — an organic compound of lead covering the surface like a varnish — the water in each case becoming nearly colorless. In No. 3 there was a visible action almost immediately, the lead turning black, owing probably to the action of the trace of nitrous acid found in this water. This action did not increase after 24 hours. The distilled water attackedi^he lead with energy and soon became filled with brilliant^mall scales of carbonate of lead, floating in the water. After two months’ similar exposure, there appeared no difference in the condition of the lead, beyond what is described as happening within twenty-four hours. No signs of corrosion were visible under or upon the brownish varnished surface, while the water, Nos. 1, 2 and 4, which had stood two months on the lead, gave hardly an appre- 3 18 ciable trace of that metal to tests. The lead from No 3, (spring water,) was sensibly corroded and was not covered as in the other cases with a varnish-like deposit; there was no organic matter in it to produce such an action. This water contained sensible quantities of carbonate of lead. The lead which had lain two months in distilled water, was very sensibly corroded, and the surface, felt rough to the touch.* I infer from these trials that either No. 1, 2 or 4 may be safely conducted through leaden service pipes, and into lead-lined cisterns, without injury to health, provided care be taken in laying down the pipes to exclude dust of lime and other rubbish which is liable in process of building to fall into open pipes. It has been shown that several cases of lead poisoning were directly referable to the presence of foreign bodies in the pipes, which lodging in the bends had favored a local action, causing the corrosion of the lead. (See the American Journal of Science, July, 1861, p. 115.) As the spring water, No. 3, can in any case form but a small part of the whole volume of the stream, it can not affect the quality of the whole water in this respect, as is conclusively shown by the result of this trial. ACID OR ALKALINE CONDITION OF THE WATERS. It may in this connection (with regard to the action of the waters on lead) be of some interest to state that neither of these water^|as found entirely neutral to tests for neutrality. Thus, Nos. 2, 1 and 4 were slightly alkaline in the order named, commencing with 2, as compared with distilled water. No. 3, as compared with the same standard, was found to be slightly acid. * These samples are presented with this Report. 19 2d. THE PROBABLE EFFECT OF STORING THE WATERS OF TROUT BROOK UPON THEIR FITNESS FOR USE, &c. The inquiry very naturally arises, will there be any unfavorable effect produced by the accumulation of these waters in artificial lakes ? I reply, if proper care is taken in the construction of the reservoirs and in cleaning up the ground which they are to cover, as well as the margins of the streams wherever they are swampy or boggy, the effect of storing the water will be to improve it in every particular as compared with the waters of the stream. The water contains, in an average state of flow, only two grains of organic matter in seventy thousand grains or one gallon of water. This minute quantity imparts to it only a feeble color and faint odor, which in the north branch of the stream are com- paratively inappreciable. The origin of this organic matter is largely in the boggy margins of portions of the stream.; these must be properly cleansed by grubbing, and with that operation the qualities spoken of will probably disap- pear, or become quite inappreciable. But there is another cause of annoyance which has made its appearance at New Britain and Danbury, where storage for water has been provided, and to which it is important to allude in this connection. At New Britain an artificial lake has been formed over a mile in length filling the interval between two trap mountains about a third of a mile apart. A small moun- tain stream had its origin from the springs which flow out at the base of these hills, a stream far smaller than Trout Brook. No stream flows into this artificial lake, which is kept quite full by the rain-fall and the flow of the springs alluded to. The area now covered by its waters was densely clothed with shrubs and many large trees which have been cleared away by the axe only. The soil was wet and boggy and the rank growths of numerous aquatic plants were left undisturbed on the swampy surface, together 20 with the stumps and roots of the trees cut away. The natural result has been that the vegetable juices flowing from such a vast steep of decomposing organic substances has, in each summer since the lake was formed, produced an unpleasant effect on the water. In such a favorable soil much confervoid growth haTs developed itself with the progress of the season, and by the last of June some of these plants, existing in great numbers, have reached their limit and Hied, producing a decomposition and the dissem- ination of many filaments of vegetable growth through the water. This trouble has reached its height by the middle of July and then rapidly disappeared. I have examined carefully into the conditions and causes of this phenom- enon at New Britain, with reference to your case, and am of opinion that it is owing wholly to the want of a proper preparation of the bottom and sides of the lake. All the organic matters alluded to, with the boggy soil, should have been removed before the ground was flooded. The very moderate capital of that enterprise, ($50,000,) forbade that expense. I am, however, quite satisfied, after two summers’ consideration and examination of this case, that the annoyance alluded to is self limited and will soon dis- appear or cease to recur after a year or two, having been in the present year limited to a few weeks, and unattended, so far as I can learn, with any detriment to health. The water at New Britain, with the exception of the brief period alluded to, is as *pure as possible, and the visitor viewing this beautiful little lake from any point where the dam is not seen can hardly credit that it is an artifi- cial lake of only three years’ standing. I am equally satisfied that, in the case of the proposed reservoir at West Hartford, the annoyance experienced at New Britain will never make its appearance if the pre- cautions alluded to are observed. GOOD SUCCESS OE STORING AT BROOKLYN. At Brooklyn, N. Y., they enjoy a very fine quality of water, gathered in collecting reservoirs from a wide surface. 21 and all the bottoms of the artificial lakes having been carefully cleaned there has been no trouble from the growth of vegetable organisms in the water. The gathering grounds about the -proposed site of the West Hartford supply are as free from objection as to sources of contamination as any which can be found. Much of the surface is a clean gravel or sand covered by a slight growth of grass, and the amount of cultivated land where drainage flows into the brook is small. I have, therefore, no hesitation in predicting that the storage of the waters of Trout Brook will be a complete success, both in the abundance and quality of the waters and the absence of any cause of anxiety, real or imaginary, as to the unfavorable effect of such storage. 3d. what precautions should be taken to secure THE BEST POSSIBLE QUALITY OF WATER FOR A CITY SUPPLY. This inquiry, in your case, does not go behind the source of supply, which has been shown to be both abundant and of the best quality, whether we refer to the Connecticut River or the new source now under consideration. The inquiry may therefore be restricted to the mode of storing and distributing the water. In all cases of supply drawn from rivers, the water dis- tributed to consumers is liable, unless proper precautions are taken to prevent it, to great variations in transparency, owing to the muddy state of the river in times of flood. The researches of Dr. Graham and others show that the * suspended matter” in the water of the N6w River, in London, is about 1.5 grains to the imperial gallon, or one- half as much as the total solid contents of all kinds in the Hartford waters as they were when these inquiries were instituted. At times, no doubt, the “suspended matters” in the Connecticut River water are as great as are found in New River. In fact, your own experience with your present city supply, in times of flood, is such as to satisfy 22 you that some precaution is indispensable to avoid the annoyance to consumers arising from this cause. You now pump the river water into a distributing reservoir of too limited capacity, which is unprovided with any means to favor the subsidence of suspended matter, much less do you filter the water. It consequently passes into the circulation in a state often quite unfit for use. This evil would be much abated if you had even two compart- ments in your existing reservoir, one as a receiving and subsiding reservoir, and the other supplied from this, or the two used alternately after allowing a certain time for subsidence. FILTRATION. But no means have yet been found so effectual in the proper preparation of water for towns as simple filtration through porous media. DIFFERENCE BETWEEN SPRING AND RAIN WATER. The chief cause of difference between “spring water” and “river water” is that the former is the result of Nature’s process of filtration through the soil and porous layers on the surface, while the river water represents the rains plus the wash of the surface. The spring, No. 3 of this report, was perfectly brilliant, colorless and brisk, but the process of filtration had been carried too far; the organic matter was almost all removed, and some new inor- ganic elements added, which render the water unsafe for use with lead. Our artificial arrangements must then be made to imitate the great processes of nature, taking care not to go too far, of which, indeed, there is little danger. Thus may we hope to turn the river into “ spring water,” as far as brilliancy and briskness go. AERATION OF WATER. The sparkling quality so highly esteemed in spring and well water, is due chiefly to the presence of atmospheric air and carbonic acid held in solution in the water. Rain 23 water recently fallen, and river water, owe their peculiar flatness to the absence more or less complete of these qualities. It is well known that rain water, by long stand- ing in subterranean cisterns, acquires to a good degree the sparkling quality of well water. The wells in the city of Yenice are all rain water cisterns, constructed in a' peculiar manner to secure the constant filtration of the water from the outer or containing cistern, into an inner, well-shaped cavity, whose bottom and sides are composed of porous stones and bricks. This arrangement is an excellent substitute for the natural process of filtration, which supplies our ordinary wells, and the water has none of the qualities of rain water, except its softness and purity. This beneficial change is due mainly to the aera- tion of the water. The storage of water in large reser- voirs, where it is permitted to stand exposed to atmos- pheric influences, produces more slowly, perhaps, but not less surely, the same desirable effects from aeration. When this mode of storage is combined with the system of filtra- tration suggested in this report, the best results may be expected. Such we hope will be the system adopted to secure the aeration of the waters of Trout Brook. STRUCTURE OF FILTERS. As but little has been made public in this country respecting the modes of filtration found effectual in the old world, I will state briefly the method adopted with much success at the Chelsea water works in London, by Mr. James Simpson. The water, after being pumped up from the river, is allowed to stand in subsiding reservoirs for six hours before it is suffered to run on to the filter beds. These are large beds of sand and gravel, each exposing a surface of 270 square feet, and the water passes through them at the rate of about 6£ gallons to the square foot of filtering surface per hour, making a total quantity of 1,687.5 gallons per 24 hour through each filter. The filters are composed of the following strata in a descending order : No. 1, Fine sand, 2 ft. 6 in. “ 2, Coarser sand, 1 “ “ 3, Shells, 6 “ “ 4, Fine gravel, 3 “ “ 5, Coarse gravel, 3 “ 3 “ These several layers of filtering materials are not placed perfectly flat, but are disposed in undulating folds, and below each convex curve of each undulation is placed a porous earthen ware tile, which conducts the filtered water into the mains for distribution. The depth of the water over the fine sand is four feet and a half. The upper layer of sand is removed about every six months, but the body of the filter has been in use over twenty-five years. Their action is extremely satisfactory — they usually remove all the suspended matter. The Thames, in flood, contains a quantity of very fine ferruginous clay, which not even a charcoal filter will remove. The Connecticut, it is believed, never contains any thing which would not be completely removed by a good filter. I do not now go into more detail as to the construction of filters and their efficacy to give a full supply, since all those points must be carefully considered in the light of abundant experience by your Engineer. There is, however, one other point worthy of note in this connection — namely, the curious and unex- pected results obtained by Mr. Witt, Chemist to the Chel- sea Water Company. This chemist found, by a series of carefully conducted analyses, that the process of filtration not only removed the suspended impurities of the water, but even withdrew dissolved salts from solution in water. This unexpected result (the details of which would be out of place here) shows the importance of filtration from a hygenic point of view, as well as from motives of general comfort and cleanliness. In regard to the storage of the waters of Trout Brook, 25 I would recommend that besides the main distributing^ reservoir, with its filtering beds, if you decide to adopt the process of filtration, there should be supplemental reser- voirs on each branch of the stream, to hold back the winter and spring floods, as well for storage as to arrest the sus- pended matter, so that the quantity of sediment should in no case become considerable in the main or distributing reservoir. If proper pains are taken in cleaning up the course of the streams and the bottom of the reservoirs, the water will, I am confident, be found well nigh colorless and completely clear at all times, unless during very heavy freshets. The vast advantages you will derive from taking in this new supply at a head adequate to reach the highest points in Hartford, without artificial help, I will not dwell on. You are happy in having at command the inexhaustible full- ness of the great river, but you may yet learn to place your main dependence upon what you now consider as only an auxiliary source, combining as it does the advantage of an ample head and flow, with superior facilities for storage and purification. I am, gentlemen, with much respect, Your obedient servant, B. SILLIMAN, Jr. New Haven, August 30th, 1861. * * REPORT Of McREE SWIFT, Esq., Civil Engineer. Jo the Board of Water Commissioners of the City of Hartford : Gentlemen : At your request I herewith submit my views on the question of securing an additional supply of water for the City of Hartford. The average daily consumption of water in Hartford for the year ending March 1, 1861, was 897,035 gallons, the extremes being 717,395 gallons daily in April 1860, and 1,028,312 gallons per day in February 1861. A basis of 2,000,000 gallons per day is therefore considered sufficient for the present and prospective population of your city. After a careful examination of the whole subject, I am satisfied that one of two plans should be adopted to secure this increased supply ; — either by increasing your present pumping facilities, and building a larger reservoir on higher ground, or by adopting the proposition to con- struct a large receiving or storing reservoir on Trout Brook in West Hartford, of elevation sufficient to deliver the requisite quantity of water into every part of the city by gravitation. As this subject has engaged your attention for a long- while, and the details connected therewith have been ex- tensively discussed, I shall confine my remarks to the comparative merits of these two projects. 4 28 By reference to the report of Prof. Silliman recently submitted to you, it will be seen that a comparison of the purity and physical properties of the water in Connecticut river at Hartford, and Trout Brook, would indicate no preference between them for all practical purposes ; both waters being remarkably pure. From personal examination of the proposed site for the reservoir on Trout Brook, I have no hesitation in saying, that the grounds are better adapted for keeping stored water in a pure state than those of any large reservoir I know of. Care must be taken to thoroughly clean the bottom and sides of the reservoir, and especially should no vegetation be allowed at the water line ; for this pur- pose I have estimated an expenditure of $5000, and with so liberal an outlay, I have no doubt the retained water would remain pure. The water supply of the Brooklyn City works, is collected in a series of reservoirs construct- ed as this is proposed to be, but with the disadvantage of less average depth, and the water is remarkably fine. As to the natural flow of water in Trout Brook, the frequent gaugings and measurements kept by your engi- neer for upwards of a year, leave not a shadow of doubt as to the sufficiency of supply ; these gaugings give a min- imum flow of 500,000 gallons in twenty-four hours, after a drouth of near six weeks duration, and a daily average for the year of over 6,000,000 gallons ; and my own ob- servation of the capacity of the stream made at three dif- ferent times, satisfy me that this estimate is not too large ; and that the supply would be equal to the demands of a population of 100,000. Thus the chemical properties and the reliability of sup- ply being about equal in the two projects, the question of preference should be decided by the comparative cost of the two. The great draft upon the distributing pipes in large cities, reduces materially the effectual head on the distri- 2 § bution— so that, at points lower than the ievel of watei* in the reservoir, no water can be obtained when the draft is large below them. This maybe observed daily in New York city, where it is a cause of great complaint, and also in your own city, especially on high portions, as at the Retreat for the Insane,* where, with a head of twelve feet, no water can be obtained from the pipes, when the low portions of the city are drawing largely. For this reason, as well as to provide a sufficient head for the highest portions of the city, Zion’s Hill has been proposed for the site of a new reservoir. The surface of water in this reservoir would be one hundred and seventy- five feet above the river, and seventy-five feet below the surface of water in the proposed reservoir at West Hartford, and fifty feet higher than your present reservoir. This reservoir should be so constructed, that with a depth of eighteen feet, it will contain at least 20,000,000 gallons, or ten days supply ; it will occupy between six and seven acres of ground, and should have two compartments, so that when the water of the river is in a turbid state, time for settling may be allowed, before it is distributed to the city ; such a division too, will enable you to keep the reservoir in a cleanly condition, a most important mat- ter. Should you conclude to adopt the plan for bringing the water from Trout Brook by gravitation, I do not consider a distributing reservoir essential, because your storing reservoir of twenty-five acres on Trout Brook, to contain 121,000,000 of gallons, would be but five miles distant, and reservoirs so located have proved sufficient for other places. The new receiving and distributing reservoir now under construction at Central Park in New York city, is more than five miles from the City Hall, and became ne- cessary in consequence of the insufficiency of the present * It is seldom that water can be drawn at this point, except at night, even with a full reservoir. — Commissioners. 80 one at forty-second street, which has a capacity of less than one day’s supply for the city. All that you would provide against by a distributing reservoir in the city, would be the remote contingency of a failure in the main pipe. Should you deem it advisable to provide for such a con- tingency, a reservoir of sufficient capacity, say 4,000,000 gallons, near Vanderbilt’s, two miles from the State House, and three miles from the Trout Brook reservoir, can be built for 118,708, which includes the connections and cost of site — two and a half acres. The calculations for the delivery of water, taken from Trout Book by a sixteen inch main, are based upon the well known formula of Eytelweyne, viz. : ^/'D x ^>0 x II _ ve i oc ity p er second ; in which D v L + (D X 50) J ^ ’ represents the diameter of pipe, H the head of water, and L the length of pipe. At the proposed reservoir near Vanderbilt’s, one hundred and ninety feet above the river, and sixty feet below the Trout Brook reservoir, and 16,000 feet from it, the delivery would be 8,182,000 gallons of 281 cubic inches in twenty- four hours. At the river in Hartford, estimating the main 26,400 feet long, the delivery would be 5,062,264 gallons, and at a point in the city ninety feet above the river, the delivery would be 4,049,741 gallons, and at one hundred and twenty-five feet above the river, the height of your present reservoir, the delivery would be 3,579,700 gallons in twenty-four hours. In order to procure the requisite supply of 2,000,000 per day, by pumping, your present facilities must be ma- terially increased, either by an alteration of your present machinery, the constructing of a new engine and pumps of sufficient capacity, or by both, and as the risk of failure to which all machinery is liable, should be as far as possi- ble avoided, particularly in so vital a matter as the water supply for a city of the present and prospective population 31 of Hartford, I would recommend you, not only to altel* your present engine so as to increase its power, but also to construct a new set of machinery, equal to the above mentioned duty of 2,000,000 per day. I understand Messrs. Woodruff & Beach have recently made you a proposal to this effect, to wit, for a total remu- neration of $33,000, 1st. To alter the present machinery, so as to make it equal to forcing 1,500,000 gallons into the proposed Zion’s Hill reservoir, through a rising main of 20 inches in diam- eter in 12 hours. 2d. To construct another engine and pumps of power sufficient to force into the same reservoir through a pipe of same diameter, 2,000,000 gallons in 12 hours. 3d. To make all necessary alterations at the present engine house to accommodate both sets of machinery. Based upon this proposition, my estimate for cost of proposed means of supply by pumping is : — For increasing capacity of present machinery, for new engine and pumps and for alter- ations at engine house, as per proposition of Messrs. Woodruff & Beach, . $33,000 For reservoir on Zion’s Hill to contain 20,000,- 000, gallons, .... 38,245 For 12,800 feet rising main, 20 in. diameter, at $2.75 per foot, . . . 35,200 For 5,700 feet return pipe through Yernon St. and Retreat Avenue, of 16 in. diameter, at $2.05 per foot, . . . 11,685 For 1,500 feet waste pipe, 12 in. diameter, at $1.25 per foot, . . 2,100 $120,230 Less 2,500 feet, 6 in. distribution pipe in Ver- non St. at $0.62 per foot, substituted by a part of the return pipe, . . 1,550 Total, $118,680 To which must be added the annual cost of forcing 2.000. 000 gallons per day, into Zion’s Hill reservoir. I base so much of this estimate as relates to the cost of fuel, oil and waste, upon information derived from the report made by the Water Commissioners of Brooklyn, Jan. 1862, where I find that 1,649,172,500 gallons of wa- ter was raised 170 feet through a main 36 inches diameter and 5,800 feet long in 3,082 hours, by an expenditure of 4,920,748 lbs. of coal, being 2,984 lbs. for each million of gallons raised ; the cost of oil, waste and tallow for this ser- vice, being at the rate of 40 cents per million gallons. So much of the estimate as relates to wages of engineer, fire- man and laborers, and the repairs of machinery, I base upon the statement in your report of March, 1861, adding thereto $360 for additional labor of coaling and attending to extra engine. The duty requisite for your proposed improvement is 730.000. 000 gallons, to be forced through a main 20 in. in diameter and 12,800 ft. long, to a height of 175 ft. in 4,380 hours, which w^ould require,' at above ratio, 972 tons — of 2,240 lbs — of coal, to which should be added 12 per ct., equal to 117 tons, to overcome increased friction incident to additional length and decreased diameter of forcing tube. The annual cost of pumping will then be : — For salary of engineer, firemen and laborers, $2,160 For fuel — 1,089 tons coal — at $5.25 per ton, 5,717 For oil, waste and tallow, . . . 292 For repairs to machinery, . . .700 $8,869 Representing a capital of . . $147,816 To which should be added the first cost, as above, .... 118,680 Total cost by pumping $266,496 33 The estimate for cost of proposed means of supply by gravitation, with a storing reservoir on Trout Brook of 25 acres, to contain 121,000,000 gallons, is, For 32,000 cub. yards of earth in dam, at 20 cts., $6,400 “ 2,000 “ “ puddle wall “ 50 “ 1,000 “ Cleaning and preparing site for Reservoir, 5,000 “ Land and damages to mill privileges,