Water-Data Report 2010 01208925 NEAR FAIRFIELD, CT Coastal Basin Saugatuck Subbasin

LOCATION.--Lat 41°09′56″, long 73°16′15″ referenced to North American Datum of 1927, Fairfield County, CT, Hydrologic Unit 01100006, on right bank just downstream from bridge on Duck Farm Rd., 1.5 mi north of Fairfield, 18.3 mi downstream from headwater of Aspetuck River, 14.0 mi downstream from headwater of Mill River, and 2.3 mi upstream from mouth at Southport Harbor. DRAINAGE AREA.--28.6 mi².

SURFACE-WATER RECORDS PERIOD OF RECORD.--October 1972 to current year. REVISED RECORDS.--WDR CT-80-1: 1973-74, 1976-79 (P). WDR CT-83-1: Drainage area. WDR CT-06-01: 1979-80, 1982-83, 1996 (P). GAGE.--Water-stage recorder and crest-stage gage. Datum of gage is 15.89 ft above National Geodetic Vertical Datum of 1929. Satellite telemetry at station. REMARKS.--Records good. Flow completely regulated by Easton, Hemlock, and Samp Mortar Reservoirs, usable capacity 609,900,000 ft³, diversions into Hemlock Reservoir from in the Aspetuck River Basin and by diversions from Hemlock and Easton Reservoirs for water supply of the cities of Bridgeport and Fairfield.

U.S. Department of the Interior Suggested citation: U.S. Geological Survey, 2012, Water-resources data for the United States, Water U.S. Geological Survey Year 2010: U.S. Geological Survey Water-Data Report WDR-US-2010, site 01208925, accessed at http://wdr.water.usgs.gov/wy2010/pdfs/01208925.2010.pdf Water-Data Report 2010 01208925 MILL RIVER NEAR FAIRFIELD, CT—Continued

DISCHARGE, CUBIC FEET PER SECOND WATER YEAR OCTOBER 2009 TO SEPTEMBER 2010 DAILY MEAN VALUES Day Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep

1 17 42 30 77 41 178 377 31 15 9.0 7.9 7.8 2 18 36 24 73 38 152 243 34 13 9.1 7.8 7.8 3 83 13 127 68 38 134 184 72 16 8.9 7.7 7.8 4 103 24 112 65 37 109 152 61 13 8.6 7.8 7.3 5 46 46 94 58 35 98 129 50 12 8.3 8.0 7.0 6 16 47 94 52 34 86 113 30 13 8.2 7.6 7.0 7 34 45 72 48 31 77 102 27 12 8.2 7.0 7.4 8 31 37 63 45 28 67 91 33 11 8.1 7.4 7.5 9 17 24 164 48 26 63 91 32 13 8.2 7.5 6.8 10 18 16 147 43 28 59 87 32 20 8.4 7.6 7.0 11 18 11 113 32 31 56 71 31 14 8.1 7.3 7.0 12 21 12 86 31 27 55 64 33 12 7.8 7.3 7.2 13 31 13 131 31 26 198 57 32 12 13 7.2 7.8 14 33 24 157 29 24 1,190 53 32 12 23 7.1 7.7 15 45 34 120 29 23 605 49 27 11 13 7.2 7.2 16 51 32 105 29 25 319 44 16 11 9.5 11 15 17 40 31 89 33 25 211 50 16 11 8.8 8.6 16 18 33 31 74 51 24 164 49 23 10 8.1 7.7 8.1 19 16 15 64 47 25 137 48 41 10 26 7.7 7.6 20 20 11 74 46 26 119 41 27 10 19 7.5 7.3 21 21 6.0 68 40 27 105 35 23 9.8 26 7.0 6.9 22 20 5.8 53 36 27 109 32 22 14 22 27 9.0 23 18 7.9 47 33 37 582 37 21 22 14 58 8.8 24 25 23 48 30 147 372 36 21 18 12 13 7.6 25 25 24 41 79 297 209 41 20 13 15 12 7.3 26 59 23 72 147 595 170 52 19 9.8 11 10 6.8 27 79 29 260 112 323 136 68 17 10 9.3 9.0 13 28 96 42 210 83 213 115 60 14 14 8.8 8.6 25 29 102 42 146 69 --- 489 49 13 11 8.9 8.4 10 30 74 26 93 57 --- 1,070 37 13 8.8 8.1 8.2 35 31 37 --- 81 48 --- 731 --- 12 --- 8.0 8.0 --- Total 1,247 772.7 3,059 1,669 2,258 8,165 2,542 875 381.4 364.4 324.1 293.7 Mean 40.2 25.8 98.7 53.8 80.6 263 84.7 28.2 12.7 11.8 10.5 9.79 Max 103 47 260 147 595 1,190 377 72 22 26 58 35 Min 16 5.8 24 29 23 55 32 12 8.8 7.8 7.0 6.8

STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1973 - 2010, BY WATER YEAR (WY) Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Mean 20.0 29.1 46.6 49.3 46.3 74.5 81.2 50.9 33.0 15.0 14.2 14.6 Max 74.1 98.7 165 176 103 263 276 216 195 71.7 63.6 42.2 (WY) (2006) (2007) (1997) (1979) (1973) (2010) (1983) (1989) (1982) (1984) (1992) (1994) Min 2.98 8.00 7.04 3.13 6.62 15.1 12.1 10.2 2.74 0.93 1.72 2.16 (WY) (1985) (1999) (1983) (1981) (2002) (2002) (1985) (1986) (1987) (1987) (1987) (1983)

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SUMMARY STATISTICS Calendar Year 2009 Water Year 2010 Water Years 1973 - 2010 Annual total 15,645.0 21,951.3 Annual mean 42.9 60.1 39.5 Highest annual mean 62.4 1984 Lowest annual mean 12.0 1985 Highest daily mean 275 Jun 19 1,190 Mar 14 2,010 Apr 16, 2007 Lowest daily mean 5.8 Nov 22 5.8 Nov 22 a0.00 Nov 7, 1979 Annual seven-day minimum 9.1 Sep 4 7.1 Sep 5 0.71 Jul 16, 1987 Maximum peak flow 1,510 Mar 14 3,450 Apr 10, 1980 Maximum peak stage 6.15 Mar 14 7.15 Apr 10, 1980 Instantaneous low flow 5.1 May 6 a0.00 Nov 7, 1979 10 percent exceeds 92 128 87 50 percent exceeds 33 28 21 90 percent exceeds 12 7.8 4.5 a Result of regulation.

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