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

Suinmai-y of month]}/ precipitation at points in Connecticut. Norwalk, 1892-1913." Jan. Feb. Mar. Apr. May. .Tune. July. Aug. Sept. Oct. Nov. Dec. Year. 3.44 0.48 1.04 3.60 7.08 .49 4.35 8.55 1.22 3.62 7. SO .77 4.09 8.53 .07 2.76 10. 54 .56 3.87 10.12 .83 5.10 11.38 .37 3.63 7.87 .98 4.03 9.09 .68 3.56 8.86 .95 3.84 8.58 .92 45.89 Maximum . . 57.85 34.88 Hartlord, 1846-1853, 1868-1908.'' Jan. Feb. Mar. Apr. May. June. July. Aug. Sept. Oct. Nov. Dec. Year. 3.47 8.48 1.08 3.43 8.28 .50 4.00 9.38 1.00 3.14 11.17 .74 3.55 3.32 4.30 15.14 1.33 4.59 10.27 .90 3.08 10.88 .25 3.85 13.33 .60 3.64 8.29 .74 3.33 9.34 .67 44.30 Maximum 9.10 10.81 .20 .15 56.36 33.64 Middletown, 1858-1902.'' Jan. Feb. Mar. Apr. May. Jmie. July. Aug. Sept. Oct. Nov. Dec. Year. Avera.se Maximum Minimum 4.22 9.24 1.45 4.. 33 7.56 . 63 4.74 3.53 9.49 13.37 1.12 1 1.09 1 3. 88 3.31 8.05 8.05 .22 .39 4.. 51 13.43 1.10 4.85 10.22 1.16 3. 67 11.64 .49 4.05 14.51 .89 4.26 9.50 .75 3.90 11.18 1.20 49.25 68.77 37.08 a Oroodnough, X. H., Rainfall in New England: New England Waterwcflcs Assoc. Jour., Sept., 1915. t U. S. Dept. Agr. AV earlier Bureau Bull. AV, section 105, 1912. JAN. FEB. MAR. APR, MAY JUNE. JULY AUf. SEPT. OCT. NOV. DEC FiGri:i; 1. — Diagram sliowing mean monthly precipitation at Norwalk, Conn., 1892-1913. Fioures 1, 2, and 3 are graphic representations of the data given in the aljove tables. SUilFACE WATERS. The iNTorwalk area is drained for the most part by streams 15 to 20 miles louff tributary to Long Island Somid, but a little of the GEOar^APTIY. 13 iioithorn part is (IraiiuHl by tributaries of lliidsoii Kivoi-. T\n\ Siidicld area is drained entirely to the Connect iciil. 'i'iie (llaston- JAN. FEB. MAR. APR. MAY JUNE JULY AU6. SEPT. OCT. NOV. DEC- I'iGiitE -. — Diagr.-im showing nicnn monthly precipitation .\t Il.iitfoid, Conn,, 1,S4(»-1853 and 186.S-1008. bnry area is in part drained by westward-flow ino- streams directly iribntary to Connecticut River and in part by southward-flowing JAN. FEB. MAR. APR. MAY JUNE. JULY AUG, SEPT, OCT NOV. DEC. Fku'uk 3. — Diagram .showing mean niontlily pn'cipitation .it MidtUctown. roni\.. l.s."').S-1002. streams that enter Salmon Eiver, whicli joins the Connecticut at East Haddam. In tlie XorAvalk area and in the highland portion of the Glastonbury area there are many lakes and ponds. Some 14 GROUND WATER IN NORWALK AND OTHER AREAS, CONN, of the swamps are former water bodies tliat have been filled w^itli sediment. When water falls, as rain or snow, a part evaporates, another part enters the ground, and a part flows off in streams. Some of the gi'ound water eventually returns to the surface in springs, seeps, and swamps and enters the streams. Some is lost by evaporation, and b}^ transpiration of trees and other plants. The ratio of run-off to rainfall varies greatly, as it depends on many factors, including the rate of precipitation, its distribution throughout the year, the character and thickness of the soil, steepness of slopes, abundance of vegetable growth, amount of frost, and character and structure of the rocks. The following tables give some idea of the amount and variations of the run-off in two basins in Connecticut : Monthly run-off of Pomperaug River at Bennetts Bridge and precipitation in Pomperaug drainage basin. '^ [Drainage area 89.3 square miles.] Month. Precipi- tation (inclies). Run-off. Inclies on drainage basin. Percent of precipi- tation. 1913. August September October November December 191-1. January February _ March April May June ■ _ July August September October November December 1915. January February March April May June July August September Year, October, 1913, to September, 1914 . 22 months for which tlie run-oil is given 3.19 3.53 9.66 3.05 2.72 2.15 2.14 5.63 4. 35 3.19 2.83 5.91 3.66 .36 3.31 3.37 2.82 6.21 5.70 .15 1.59 3.37 2.01 6.31 8.09 2.94 45. 65 80.20 0.25 .35 2.57 2.73 2.24 1.33 .58 4.32 2.94 2.35 .63 .70 .45 .20 .51 1.61 1.60 1.21 .45 .78 1.79 .92 38.95 48.41 6.8 9.9 26.6 89.5 81.7 61.8 27.1 76.6 67.5 73.6 22.3 11.3 12.3 55.6 14.8 1,070.0 100.6 35.9 22.4 12.4 22.1 31.3 85.4 60.4 oData obtained from unpublished report by A. J. Ellis, U. S. Geol. Survey. GEOCiltAPH V 15 I'l If ii)it(tti<i)i iiikI niii-dff ill lloHsiitonic ilidiiiai/c ha-siii iiborc ddnhinlavillc, Co, UK. t'.KU-t'l'l.l. iiinl 1>)<Hi-l*)0'.i." [!'i:iiimi;.' ', I .iilO s([iiaio mi'.os. Piecipi- tatioii (inches). ■Run TiU'lios oil <li'aina;,'r busiii. o/r. Year. Ppr cent of ])rocipi- tution. 1901 56.94 61.43 f)6. &5 46.31 55. 80 40.26 44. 75 29. 65 38. 62 .■59. 6.5 22.17 29.47 19. 67 19.^5 52.1 1902 (>2. 9 i9o:i . 69. 8 1906 47.0 1907 52.9 1908 . 48.8 1909 44.4 oCompiled from Gregory, H. E., and Ellis, E. E., Undcrground-vt'ater resources of Connecticut: U. S. (ipnl. Siirvpv Water-Snppiv Paper 232, p. 29, 1909; and from Surface-water supply of tlie I'nited States, 1907-8 Parti, and 1909, Part I: U. S. Geol. Survey Water-Supply Papers 241 and 261. Tlu> Tenth Census i-epor( on water power gives figures taken from various sources concerning the ratio of run-off to precipitation in a nnmlver of drainage basins. The data for four of these basins in the nortlieast-ern United States are summarized in the following tal)le : Prrcii)itafif)ii <nuJ nin-off in ccrtfiiii (lidiinn/c Jidxiiis- in ihc Dorfhrasimi T^iiilcfl Basin. Area c.( basin (square miles). Length ol record (years). Aiinua! precipi- tation (inches). Average run-cff (per cent ' f precipitatirni. Mean. Maxi- mum. Mini- mum. Connecticut River above Hartford 10,234 78 20.37 339 7 5 13' 42.7 46.1 50 ■!9. 79 62.? 47.6 62. 9 .56. 5 Sudbury River 1 West Branch of Croton River. . Crcton River "Months. The difference in the per cent of run-off' from tlie basin of the West Branch of Croton River and from the whole Croton drainage }>asin is due to the fact that tlie former is a steep, rocky, thin-soiled, and relatively untilled region, Avhereas tlie latter includes much flat-lying and cultivated land and therefore absorbs more of the rain. WOODLANDS. The woodlands of the Xorwalk area occupy aoout 38 per cent of the total area and for the most part comprise deciduous tree species. The most prominent trees are oak, hickory, chestnut, elm, maple, beech, and birch, with a few conifers. The Avoods are more abundant away from the Sound shore. The three shore towns, Darien, Nor- 16 GROUND WATER IN NORWALK AND OTHER AREAS, CONN. walk, and Westport, are about 25 per cent ATooded, and tlie four in- land towns, New Canaan, Ridgefield, Weston, and Wilton, are about 45 per cent wooded. The Suffield area is about 38 per cent wooded, and its most cleared portions lie along Connecticut River. ]\Iany of the stands on the loAvland plains comprise chie% white and yelloAT pine and scrub oak, with an undergrowth of sweet fern and " poverty " grass. The flora on the hills is of the deciduous type like that of the Xorwalk area. The Glastonbury area is about 63 per cent wooded and contains chiefly deciduous trees. There are extensive cleared tracts along Connecticut River, but the eastern part of the area is nearly all wooded. The town of Marlboro is about 80 per cent wooded. In these areas, as throughout other parts of Connecticut, a great amount of cordwood and a good deal of lumber are produced. The manner of cutting has heretofore been very wasteful, and few at- tempts at reforestation have been made. Cut-over lands have been allowed to grow up with sprout and staddle, and the woodlands have in consequence deteriorated steadily. In the last decade, however, there has been some sj^stematic planting of forest trees, and the cut- ting has been a little less ruthless. The wood crop would be very profitable Avere the industry prosecuted in a proper manner, as the soil is in general veiy good, and if given a chance will mature most kinds of trees sufficiently for the market in 20 or 30 years. POPULATION. Population of certain, toirns in Connecticvt. Area (square miles). a Population. & Towa. 1900 1910 Per cent gain. Inhabit- ants per square mile, 1910. Norwalk area: Dai'ien 12.63 22.86 22,68 35.44 20.27 19.63 28.08 17. 72 34. 25 43.31 8.15 .54. 16 22.97 3,116 2,968 19,932 2,626 840 4,017 1,598 684 6,699 3, 521 3,062 4.260 '322 3,946 3,667 24,211 3,118 831 4,259 1,706 797 9,719 3,841 3,715 4,796 302 27 24 21 19 6 7 17 45 9 21 13 312 160 Norwalk . . . 1,068 Ridgefield 88 42 Westport 217 Wilton 61 Sufliold area: East Granbv 45 Enfield ' . 284 Suffield.- 89 456 Crlastonbury area: 89 Marlboro. . 13 a Areas mcasm-ed wth planimeter on topographic maps. b Population figures from Connecticut State Register and Manual, 1919. c Loss of 1 per cent. (i Loss of 6 per cent. GROU^n) WATER IX XORWALK AND OTHER AREAS, CONN. 17 GEOI.OOH IIISI<^I?V. Very little i^=: Icnowii of tlio oai-jy £io<)l()oic history of ("onneeticut, for the rocks are veiy old and havo suti'ei'ed .so many changes that the evidence given by them is almost impossible to interpret. It is certain that in ))re-C'anibiian and early Paleozoic time sediments were deposited. The earliest were sands, muds, and clays, which became consolidated to form sandstone and shale, bnt later some limestone was deposited. Xo fossils have l)een found in these rocks, but they have been referred to the late Cambrian and early Ordovi- cian bj'- studj'ing the relative positions of the formations and by tracing them into )egions where more evidence is to be had. Sedi- ments were also deposited during the Carboniferous and very prob- al)ly in the intervening periods as well.