Ground Water in the Norwalk, Suffield, and Glastonbury Areas, Connecticut

The stratified drift of the broad valley east of Saugatuck Kiver in the northAvestern part of the town and that west of Saseo Brook seem i)robably to be of glaciofluviatile origin. When the glacier receded from this region many streams of melt water flowed from it and carried heavy loads of debris, which were deposited in front of the glacier. These deposits may, however, bo later deposits analo- gous to the alluvium of the flood plains of the present streams. The principal reason for supposing them to be glacial outwash is 'that they extend 40 or .lO feet above the present stream level. In a zone a mile or so wide along the shore of Long Island Sound are deposits of stratified drift which may be of marine origin and analogous to the present sands and gravels of the beaches. In the ])resent discussion the origin of these deposits is of less importance than their character and distribution. The map (PI. Ill) shows the areas of stratified drift. The stratified drift is formed in large part by the reworking of the till. The porosity in terms of tlie percentage of the whole volume not occupied by sand or other grains is greater than in till, and the individual pores are larger, so that the circulation of ground w^ater is greatly stimulated. Wells dug in stratified drift are likely to yield more abundant supplies than wells dug in till. Fourteen such Avells were visited in AYest- port and of these eight were said to be nonfailing. The data col- lected are given in detail in the table on pages 116-117 and are sum- marized in the followinji table : fSKJinnari/ of irclls in -^1 ratified drift in U'c-s7po/f. MaxiJiium Minimum Average.. Total Depth to depth. water. Fed. Frft. 27.8 26.4 S. .i 6.4 17.1 LVO Depth of water in well. Feet. 3.9 1.0 2.1 QUALITY OF GROUND WATER. The accompanying table gives the results of two analyses and four assa3s of samples of ground water collected in the town of Westport. Xos. '24. 52, and 56 are very "soft and low in mineral content : the rest are soft and only moderately mineralized. In so far as cliemical analysis may be used as a criterion the waters are acceptable for domestic use. No. 24, however, is so high in nitrate 154444°— 20 8 114 GKOUlsTD WATER IN NOEWALK AND OTHER AREAS, CONN. that a sanitary inspection would be warranted. Nos. 49 and 55 are a little high in scale-forming ingredients and are therefore rated as fair for use in boilers, but the rest are probably good for boiler use. Nos. 24, 39, and 56 are sodium-carbonate waters, Nos. 49 and 52 are calcium-carbonate in type, and No. 55 is a calcium-chloride water. Sample 39 was collected from a well dug into sandy soil a few hundred feet from the shore at Compo Beach. It is probable that the relatively high chloride content, 30 parts per million, is due to the proximity to salt water and frequent blowing over of salt spray, and not to pollution by either salt water or sewage. The low value of the nitrates and the cleanly surroundings of the well indicate that the water is not polluted by sewage. Sea water contains about 3.3 per cent of dissolved matter, of which about 55 per cent is chloride. This is equivalent to 1.815 per cent, or 18,160 parts per million. A mixture of one part of sea Avater with about 600 parts of pure water would contain about 36 parts per million of chloride. Therefore it seems more reasonable to ascribe the high chloride in this well to salt spray blown onto the surrounding soil and leached out than to infiltration of sea water. Cliciiiical coniijositioii and classification of ground iraters in Weslport." [Parts per million: collected Dec. S, 1916; analyzed by Alfred A . Chambers and C. H. Kidwell. Numbers , , of analyses and assays correspond to those used on PI. II.] Silica (SiOs) Iron(Fe) Calcium (Ca) Magnesium (Mg) Sodium (Na) Potassium (K) Carbonate radicle (COi) Bicarbonate radicle (HCOs) — Sulphate radicle (SCj) - . Chloride radicle (Cl) Nitrate radicle (NO3) Total dissolved solids at 180° C , Total hardiiess as CaCOs , Scale-forming constituents «... Foaming constituents «. Chemical character Proljability of corrosion / - Quality for boiler use Quality for domestic use. Analyses. 6 19 .12 8.9 2.1 \ t 17 .0 34 18 7.0 14 104 e31 49 46 Na-COs (?) Good. Good. d39 Assays. 11 .32 22 6.0 f 32 I 4.7 .0 90 49 30 4.4 218 e 80 86 100 Na-COs (?) Good. Good. 0.35 e23 100' 17 10 « 150 68 95 60 Ca-COa N Fair. Good, 0.46 ell .0 38 10 8.4 32 55 30 Ca-COs (?) Good. Good. C17 27" 27 49 « 170 85 110 50 Ca-Cl (?) Fair. Good. Trace. .0 45 i 12 7.4 e93 32 40 Na-COa N Good. Good. a For location and other descriptive information see pp. 115-117. 6 For methods used in analyses and accuracy of results see pp. 52-60. c Approximations; for methods used in assays and reliability of results see pp. 52-60. d Collected Dec. 9, 1916. « Computed. / Based on computed quantity; (?)= corrosion uncertain, N=noncorrosive. PUBLIC WATER SUPPLIES. The Westport Water Co. has been supplying water since 1892. The source of supply at present consists of two wells (Nos. 66 and 67, WESTPORT. 115 PI. II) dug in the stratified drift of the flood plain of Saugatuck Kiver a little north of tlu' vilhigc Water is pumped from these wells by two Gould triplex, singlo-uotiug pumps vritli 8 by 10 inch cylinders, driven at 40 revolutions a minute by electric motors. There is also an auxiliary direct-acting Blake steam puuip. The water is deliyered to a 240,000-gallon steel staudpipe on a hill half a mile north of the village. From the standpipo the water runs by gi-aA'ity through 20.2 miles of main to 81 hydrants and 544 service taps, of which 370 are metered. The normal pressure is 00 to 65 pounds to the square inch, but by pumping direct into the mains it may be increased to 90 pounds for fire sei-vice. Of the 3,400 people in the area served, about 3,200 are supplied and consume about 240.000 gallons a day. According to Mr. F, B. Hnbbell, the superin- tendent of the company, the wells are dug in moderately coarse gravel. The "old" well (No. 66) on the east side of the Saugatuck is rectangular, 20 feet wide and 40 feet long, and 10 or 11 feet <leep. It usually contains G or 7 feet of water. The " new '" well {So. 67) is on the west side of the Saugatuck and is connected with the pump- i)ig plant by a suction main a quarter of a mile long. This well is circular, 30 feet in diameter, and about the same depth as the older well. The wells will yield together about 50,000 gallons an hour.^ Both wells are roofed to keep out wind-blown foreign matter and the water is effectually filtered in percolating through the sand and gravel of the flood plain. The water is of good quality and is of suf- ficient abundance to care for a slowly growing population. At all events the flood plain of Saugatuck River can be made to yield muck more water by the construction of additional wells. KECoims or wells. Wells dug in till in Westport. Xo. on PI. IT. O^vner. Topo- graphic situation. Ele- va- tion above sea level. Total depth. Depth to water. Depth of water in well. Rig. Remarks. 1 Slope ...do Feet. 1(50 100 80 115 230 230 190 205 125 150 125 135 120 130 Fat. 23.9 18.6 16.0 10.8 23.0 20.5 15. 9 20.4 19.7 25. 5 15.2 23.0 29.5 17.5 Feet. 12. 5 16.0 14.6 8.3 21.4 19.2 9.7 16.6 16.8 18.4 13.2 21.2 24.1 14.6 , Feet. 11.4 Two-bucket ri^'.... 2. 6 Two-bucket r i g and house pump. 1. 4 Two-bucket rig. . . . 2.5 do 1.6 Windlnssrif s 9 ...do ...do Xon'.ailing. 10 ...do Fails. 11 ...do 1.3 6.2 do .\ Do. 12 Swale Plateau Knoll Plateau Slope . .. do Onp-hnekAt rif 14 F. L. Church.... 3.8 . ... T ... 15 2.9 Windlass rig 7. 1 Two-hncket. rii? Non failing 16 !7 2.0 1.8 5.4 do bottom. Fails IS do 19 Plateau ...do do 20 2.9 1 do Abandoned. 1 Connecticut Public Utilities Commission Kept., 1917 116 GKOUND WATER IN NORWALK AND OTHER AREAS, CONN. Wells (lug in till in West port — Continued. G. P. Jennings.. Topo- graphic situation. Slope. ..do.. .do. .do. .do. ..do.. ..do.. ..do... Hill... Slope. ..do., do.. .do. ..do ..do Hilltop. Plateau. Slope .do. ..do.. Plain. Slope. Plain. Slope ..do.. .do. .do. -do. .do. .do. .do. Ele- va- tion above sea level Plain. Total depth Feet. 90 175 120 190 120 100 105 95 60 45 80 .55 20 30 140 130 10 130 Feet. 24.0 16.4 11.3 18.4 17.5 IS. 9 13.6 24.5 17.9 14.1 14.8 18.3 18.4 26.0 12.6 31.9 19.0 27.6 12.1 14.1 12.9 11.0 16.1 10.0 10.5 11.0 19.8 14.8 20.0 11.1 15.4 Depth to water. Feet. 19.8 14.9 9.0 16.9 13.5 17.3 6.9 23.2 17.0 12.0 12.5 10.3 16.0 20.8 11.9 21.2 15.2 24.8 10.4 10.6 9.6 10.1 13.8 8.0 9.9 9.7 17.6 12.5 14.8 9.2 14.4 Depth of water in weli; Feet. 4.2 1.0 2.3 1.5 4.0 1.6 6.7 1.3 0.9 2.1 2.3 8.0 2.4 0.7 10.7 3.8 2.8 1.7 3.5 3.3 0.9 2.3 2.0 0.6 1.3 2.2 2.3 5.2 1.9 1.0 Rig. Windlass rig Two-bucket rig and house pump . Two-bucket rig Two-bucket rig and air-pressure system. Two-bucket r i g andhousepump. Two-bucket rig ....do House pump Chain pump Two-bucket rig do do. Chain pump and house pump. Chain pump Two-bucket rig. . . . •Chain pump Two-bucket rig Windlass rig and house pump. Chain pump and house pump. Sweep rig Two-bucket rie do Chain pump , do , Two-bucket rig. . . Chain pump Windlass rig Two-bucket rig Two-bucket r i g and house pump. Chain pump Two-bucket rig and house pump. Windlass rig Remarks. Nonfailing. Nonfailing. Rock bottom. Do. Do. Do. Do. Fails. Do. Nonfailing. Do. Fails. Do. NonfaiUng. Rock 10 feet. Nonfailing. Do. Do. Fails. Nonfailing Fails. Do. Nonfailing. For assay see p. 114. Fails. Rock bot- tom. Fails. Nonfailing. Do. Do. Do. Do. Wells- dug in stratified drift in Westport. No. on PI. II. Owner. Topographic situation. Ele- vation above sea level. Total depth. Depth to water. Depth of v/ater in well. Rig. Remarks. 2 Plain Feet. 135 130 160 55 75 15 20 55