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

The water-bearing properties of these four types of bedrock are alike and may be discussed together. These rocks have very little porosity, and no interstitial water is to be expected. The spaces between the grains are so minute that they can contain but little water, and their narrowness tends to increase friction and so retard circulation. The mechanical stresses to which the rocks, have been subjected have made many openings in them. These openings may be recognized as intersecting systems of joints and fissures. In gen- eral one set is horizontal or slightly inclined and is cut by one, two, or more vertical or steeply inclined sets of crevices. Their mutual intersection forms a ramifying and interconnecting network of channels through which water may circulate. Water from the satu- rated base of the overlying soil finds its way and circulates through the network of fissures and may be recovered by means of drilled wells. The data available concerning such wells in Wilton are given in the table on page 124. Till, — Till forms the mantle rock of most of Wilton. It is the product of direct glacial action and consists of the debris plucked and scraped up by the ice. The fragments have been carried along in the WILTON. 121 ice, rubbetl ii<i;;iinst one another and against the rock hetl on which the ice moved, and thus worn and polished and eventually deposited in a hetero<!;eneous mass. Pebbles, cobbles, ami boidders are embeilded in a dense matrix of the finely ground rock. The whok; mass is a very tough material, in part because of the compacting and pressing by tlie Aveight of the overlying ice and in part because the angular grains intorh)ck. This, interlocliing also tends to reduce tlie porosity of the till, for the smaller particles are fitted into the interstices of the larger ones. There is, however, much pore space, for the till absorbs, stores, and transmits large amounts of water. Wells, dugs into till Avill in general j^rocure supplies of water sufficient for domestic and farm needs. During late October and early November, 1916. 46 such wells were visited in "Wilton. Tavo were dry at the time, 10 more were said to fail, and '25 to be nonfailing. The reliability of the remaining 9 could not be ascertained. The data obtained are tabu- lated in detail on pages 122-12'^ and are summarize in the folloAving table: Sinuintni/ of ircZ/.s <litf/ in fill in Wilton. Maxiniuni - Minimum . Average... Total depth. Depth 1 0 water. F((t. 34.1 7.0 17.0 Frrt. 30. 9 4.2 13.6 Depth of water in \ well. { Frrt. S.7 .4 3.1 jSf/rifJfied (7/*//Y.— There are narrow areas of stratified drift along parts of the valley of Xorwalk River, and also in two broader val- leys, one near Bald Hill Street and one near Chestnut Hill. The distribution of these areas is shown on the map (PI. III). Streams Avhich have eroded the till have sorted and washed the constituents and redeposited them in the lowlands. The principal difference be- tween the two deposits is that the individual beds of the stratified drift contain only grains that have a narrow range of variation of size. The smaller grains have been removed, so that the interstices of the larger ones are open, and therefore the stratified drift is far more porous and a better water bearer than the till. Wells in the stratified drift are apt to give more abundant supplies than wells in till. Data were obtained concerning two driven and eight dug wells in stratified drift in Wilton. All are said to be nonfailing. The data collected are tabulated in detail on page 123 and are summarized in the following table : StniiiiKiri/ (if ircUx in stratifiid drift in Wilton. Ma.ximum . Minimum . A verage . . . Total depth. Frrt. 21.3 9.7 l,-,.4 DepthtolS^^J water water m well. Feet. 19.8 i S.O 13.3 ' Frrt. 5.0 1..5 2.5 122 GROUISTD WATER IN NOR WALK AND OTHER AREAS, CONN. QUALITY or GROUND WATER. The following table gives the results of two analyses and three assays of samples of ground water collected in the town of Wilton. The Avaters are all low in mineral content and are soft except Nos. 56 and iGA, which are very soft. All are suitable for use in boilers and so far as ma,v be judged from their chemical composition are acceptable for domestic use. Nos. 29 and 43 are calcium-carbonate in type, and the rest sodium-carbonate. CJt.einical coinpo.sitio)t and cJa^^rficatlon of (jrotuul waters in Willoii." [Partsper million; collected Dec. 8, 1916; aualyzedby Alfred A. Chambers and C. 11. KidAvell. Numljcrsof analyses and assays correspond to those used on PI. II.] SilicaCSiOs)......... Iron (Fe) Calcium (Ca) Magnesium (Mg) Sodium and potassium (Na+K)f' Carbonate radicle (CO3) Bicarbonate radicle (IICO3) Sulph ate radicle (SO 1) Chloride radicle (Cl) Nitrate radicle (NO3) Total dissolved solids at 1X0° C . . Total hardness as CaCOs Scale-forming constituents 'i Foaming constituents <' Chemical chai'acter Probability of corrosion ^ Quality for boiler use Quality for domestic use Analyses. t Assays. 42 27 .38 1.3 4.9 16 .0 .58 16 16 1.2 124 d r:.i 74 •13 Na-COa (?) Good. Good. 10 .04 8.0 3.6 12 .0 37 20 0.2 . 44 82 d 35 40 32 Na-COa (?) Good. Good. 11 2.4 70 11 rfllO 57 30 Ca-COs N Good. Good. 43 0..58 8 .0 02 12 .5.2 diOO 54 SO 20 Ca-COs (?) Good. Good. 0.80 .-..0 4.0 d70 18 45 30 Na-COs N Good. Good. a For location and other descriptive information see pp. 122-124. b For methods used in analysis and accuracy of results sec pp. 52-00. c Approximations; for methods used in assays and reliability of results see pp. 52-00. d Computed. <: Based on comjnUcd quantity; (?) = corrosion uncertain, N=noncorro3ivc. RECORDS OF WELLS. Well': 'lug in till in Wilton. No. on ri.TI. OvmcT. Topo- graphic situation. Ele- Depth vation Total depth. Depth of above sea to water vrater in level. well. Feet. Feet. Feet. Feet. 323 10.2 8.1 2.1 400 15.1 14.0 1.1 590 9.9 9.0 .9 595 11.7 8.4 3.3 600 12.6 9.0 3.6 550 25.5 20.2 5.3 575 2S.1 21.6 6.5 530 13.7 11. 0 2.7 530 23.8 15.1 8.7 465 10.9 7.6 3.3 480 34.1 30.9 3.2 610 17.1 16.5 .6 605 17.0 14.5 2.5 .520 12.4 10.4 2.0 610 21.0 16. Z 4.8 .560 15.8 14.0 1.8 Rig. Remarks. Gco.W frcy. God- Plain. Slope , do do.-.. do--.- do.-.. Ridge , Plateau — Slope .....do.... do---. do---. Ridge Slope -.- Ridge... Hilltop . . Sweep rig Chain pump . . . Sweep rig Two-bucket rig . Sweep rig Windlass rig . . . Two bucket rig . do Chain pump . . . Sweep rig Two-bucket rig . Sweep rig T. Two-bucket rig . .do. .do- .do. J^ontailing. Fails. Do. Nonfailing. Tiled. Nonfailing. Do. Do. Do. Fails. Fails. Rock, feet, Nonfailing. Fails, Nonfailing. WILTON. Wrlls iJufj in till in Wilton — Continued. 123 No. on ri.II. 27 27.V 29 30 ;iOA M 32 33 34 35 36 39 40 41 Topo- graphic situation. .Slope. . do.. do.. E dw. W. I do.. Ol instead. do Hilltop . .do- SIopc. . do. do. .do. .do. .do. .do. Plateau. Slope- .. do-. do- do. PUun.. Slope.. do. .do. .do. do. do. do. do. do. do. Swale.. Slope . - Ele- vation ,., . , level. I Feet. 390 .MO 470 420 460 330 340 245 2S0 275 375 370 360 365 290 210 280 260 280 315 380 275 265 290 225 260 235 285 355 Feet. S. 5 15.5 20.0 19.1 12.3 7.0 IS. 5 16.5 11.4 13.2 18.9 IS. 2 21.6 12.3 13.6 15.1 19.1 22.7 12.2 29.2 22.3 31.6 18.0 15.4 14.6 14.0 1.5.5 2L1 8.9 25.5 Dei>th lo water. Fed. 5.6 11.9 19.6 18.4 17.0 4.2 17.5 13.2 9.9 6.2 14.7 14.0 18.2 8.3 8.1 13. 5 18. 5 21.0 9.S 23.6 13.4 U.S 10.9 9.3 12.7 18.1 6.1 Depth of water in well. Feet. 2.9 3.0 :4 2.8 1.0 3.3 1.5 7.0 4.2 4.2 3.4 4.0 5.5 1.7 2.4 r>. .J Dry. 1.0 3.6 3.7 4.7 2.8 3.0 2.8 Dry. Sweep rii,' Chain pump. . . . Two-bucket lig . No rig Windlas.': rig and gravity .system. Two - liiicket rig and house jiunip. IIou.se pump No rig Two-bucket rig . . . Chain pump do Two-bucket rig Sweep rig and house pump. Two-bucket rig . . . do Windlass and pul- ley rig. Tv%o-buckct rig. . . do do Windlass riu Remarks. Nonlailiug." Fails. Fails. Rock, 6 feet. Nonfailing. Do. For 122. Two-bucket rig W'indlass rig . . One-bucket rig do Two-bucket riy do do No rig Windlass rig. . Chain pump . . Do. Fails.6 Nonfailing. assay see p. Nonfailing. t" Do.f Do. Do. Nonfailing. Do. Fails. Nonfailing. Fails. Rock bot- tom. Nonfailinr. Rock, 4 feet. Fails. Rock, 22 feet. Nonfailing. Do. Do. Do. Fail Do. n In a depression filled with till between two rock ledges. b Rock bottom well, on slope above well No. 27, and 150 feet distant <■ Well No. 30 southwest of house; No. 30A , northeast. irc//.s- dug in ."it ratified drift in V.'Uton. No. on PI. II. 44 45 46 46. \ Martin Harbs . New York, New Haven & Hart- ford R. R Irving Pleasant . do Topo- graphic situa- tion. Slope. Plain. do. do. Slope.. Miss U.S. Willing. Plain-.. do.. do.. Eleva- tion above sea Total depth. level. Feet. Fed. 180 21.3 205 9.7 180 12 195 18.0 180 15.9 175 18.5 175 18 ISO 11.5 165 11.2 135 17.8 Depth to water. 16.5 14.0 17.0 13 9.0 9.5 13.0 Depth of water in well. Rig. Fed. Fed. 19.8 1.5 Windlass rif and house 'i pump. 8.0 1.7 Deen-well pump. Pitcher pump. 1.5 1.9 1.5 Chain pump Two-bucket rig. do Pitcher pump. . 2.5 j Two-bucket rig 1.7 ! do 4.S I do Remarks. Nonfailing Nonfailing. analysis 122.* Nonfailing. en well assay see Nonfailing Do. Do. Nonfailing. en well. assay see Nonfailing Do. Nonfailing analysis 122. For ce p. . Driv- . For p. 122. DriV' For p. 122. . For see p. 124 GROUND WATER IN NOR WALK AND OTHER AREAS, CONN. Drilled iveUs in Wilton. No. on PI. II. O^ATier. Topo- graphic situa- tion. Eleva- tion above sea level. Total depth. Depth to rock. Depth to water in well. Dia- meter. Yield per minute. ; 2 John Ilollowell School Slope do. . Feet. 320 350 465 440 370 315 360 350 375 365 550