CONNECTICUT RIVER BASIN 01192883 COGINCHAUG RIVER AT MIDDLEFIELD, CT LOCATION.--Lat 4131'12", long 7242'23", Middlesex County, Hydrologic Unit 01080205, on right bank just upstream from Cider Mill Road, 0.5 mi northeast of Middlefield, and 0.75 mi upstream from Wadsworth Falls. DRAINAGE AREA.--29.8 mi2. PERIOD OF RECORD.--October 1961 to December 1980, published as "at Rockfall", December 1980 to current year. REVISED RECORDS.--WDR CT-83-1: Drainage area. GAGE.--Water-stage recorder. Datum of gage is 134.17 ft above sea level. Prior to Dec. 2, 1980, water-stage recorder at site 2.0 mi downstream at datum 73.01 ft lower. REMARKS.--Records good except for periods of estimated record, which are fair. Infrequent regulation from Beseck Lake. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1997 TO SEPTEMBER 1998 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 3.3 26 37 e96 77 108 63 50 61 166 8.5 11 2 3.0 62 37 e74 69 104 115 75 63 213 7.6 8.9 3 2.9 73 42 64 64 91 137 88 76 173 6.5 7.8 4 2.9 46 41 62 61 80 104 75 70 120 5.6 6.9 5 3.1 12 41 62 75 70 80 62 52 80 4.8 6.0 6 2.9 11 41 58 91 62 67 73 34 53 4.4 5.2 7 2.5 11 39 57 e80 57 59 135 26 39 3.9 5.3 8 2.3 10 37 113 e70 55 54 150 22 32 3.5 8.0 9 2.1 9.3 35 186 e60 321 56 162 20 29 3.2 7.4 10 2.0 9.7 34 186 57 858 180 310 18 27 3.0 6.8 11 2.0 19 33 139 54 548 223 487 16 24 3.2 5.9 12 2.0 26 32 101 176 312 158 434 18 21 3.9 5.1 13 2.0 29 26 83 257 205 105 311 48 18 3.9 4.3 14 2.0 26 27 74 195 152 81 220 82 16 3.7 3.6 15 2.0 21 e24 69 e103 140 69 157 97 14 3.4 3.4 16 2.1 17 22 70 e79 123 63 115 104 13 3.0 3.4 17 2.2 17 21 76 e70 102 69 88 85 12 13 3.3 18 2.2 18 22 75 197 91 90 72 57 14 26 3.2 19 2.3 17 22 67 300 203 85 60 41 13 29 3.1 20 2.3 17 23 61 238 381 117 50 36 13 20 3.0 21 2.4 17 23 56 172 300 119 43 61 12 12 2.8 22 2.5 16 e21 50 126 229 94 37 64 11 8.3 14 23 2.5 15 32 58 98 179 75 33 55 12 6.5 21 24 2.6 14 41 441 162 152 83 30 42 14 5.6 22 25 5.6 19 72 571 273 131 84 32 33 13 4.5 18 26 7.3 43 107 355 224 111 79 39 28 11 26 12 27 14 72 106 e232 157 99 93 37 24 9.8 55 10 28 16 78 81 165 116 88 84 31 21 8.7 55 11 29 15 60 e65 124 --- 79 67 26 19 8.4 36 9.0 30 12 44 126 102 --- 70 56 26 66 7.3 21 8.3 31 9.3 --- e133 88 --- 63 --- 29 --- 8.3 14 --- TOTAL 137.3 855.0 1443 4015 3701 5564 2809 3537 1439 1205.5 404.0 239.7 MEAN 4.43 28.5 46.5 130 132 179 93.6 114 48.0 38.9 13.0 7.99 MAX 16 78 133 571 300 858 223 487 104 213 55 22 MIN 2.0 9.3 21 50 54 55 54 26 16 7.3 3.0 2.8 CFSM .15 .96 1.56 4.35 4.44 6.02 3.14 3.83 1.61 1.30 .44 .27 IN. .17 1.07 1.80 5.01 4.62 6.95 3.51 4.42 1.80 1.50 .50 .30 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1981 - 1998, BY WATER YEAR (WY) MEAN 36.6 66.1 86.9 80.9 91.7 102 108 60.8 54.7 18.2 22.9 14.1 MAX 130 121 237 144 162 206 284 172 242 61.3 73.6 41.2 (WY) 1990 1997 1997 1982 1981 1983 1983 1989 1982 1984 1991 1989 MIN 4.43 28.5 19.4 8.43 46.1 47.8 25.4 16.2 5.20 2.45 2.07 2.56 (WY) 1998 1998 1996 1981 1987 1981 1985 1986 1988 1987 1981 1995 e Estimated. SUMMARY STATISTICS FOR 1997 CALENDAR YEAR FOR 1998 WATER YEAR WATER YEARS 1981 - 1998 ANNUAL TOTAL 16059.8 25349.5 ANNUAL MEAN 44.0 69.5 62.7 HIGHEST ANNUAL MEAN 95.6 1984 LOWEST ANNUAL MEAN 30.8 1985 HIGHEST DAILY MEAN 335 Jan 26 858 Mar 10 1670 Jun 6 1982 LOWEST DAILY MEAN 1.7 Aug 2 2.0 Oct 10 .38 Aug 22 1988 ANNUAL SEVEN-DAY MINIMUM 1.8 Sep 22 2.0 Oct 9 .74 Aug 20 1987 INSTANTANEOUS PEAK FLOW 922 Mar 10 2260 Apr 16 1996 INSTANTANEOUS PEAK STAGE 9.98 Mar 10 12.46 Apr 16 1996 INSTANTANEOUS LOW FLOW 1.9 Oct 11 a.30 Aug 2 1964 ANNUAL RUNOFF (CFSM) 1.48 2.33 2.11 ANNUAL RUNOFF (INCHES) 20.05 31.64 28.61 10 PERCENT EXCEEDS 103 163 140 50 PERCENT EXCEEDS 29 41 37 90 PERCENT EXCEEDS 2.9 3.5 4.3 a Site and datum then in use - downstream station "at Rockfall".