CONNECTICUT RIVER BASIN 01186500 STILL RIVER AT ROBERTSVILLE, CT LOCATION.--Lat 41o58'04", long 73o02'04", Litchfield County, Hydrologic Unit 01080207, on left bank 1,500 ft down stream from Sandy Brook, 1 mi southeast of Robertsville, 1 mi northwest of Riverton, and 1 mi upstream from mouth. DRAINAGE AREA.--85.0 mi2. PERIOD OF RECORD.--July 1948 to September 1967, July 1969 to current year. REVISED RECORDS.--WSP 1901: 1948-60. WDR-CT-83-1: Drainage area. GAGE.--Water-stage recorder. Datum of gage is 510.24 ft above sea level. REMARKS.--Records good except for periods of estimated record, which are fair. Several measurements of water temperature and specific conductance were made during the water year and are listed in the miscellaneous specific conductance and temperature determinations tables. Flow regulated by power plant, Mad River and Sucker Brook Detention Reservoirs, and Highland Lake. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1994 TO SEPTEMBER 1995 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 63 53 206 299 135 272 128 99 88 10 9.7 3.1 2 64 65 171 330 128 206 113 90 62 14 11 3.1 3 59 65 141 259 116 154 110 83 52 22 26 2.8 4 47 74 137 208 107 119 111 68 53 7.8 14 2.9 5 44 58 397 172 e105 107 120 75 54 8.2 83 3.3 6 40 62 531 e158 e103 115 101 75 46 9.0 242 3.0 7 39 68 341 305 e101 148 102 70 31 18 138 2.7 8 40 48 286 292 e98 409 100 60 40 15 79 2.4 9 37 48 229 217 e94 998 111 62 21 12 49 2.6 10 45 73 192 169 e91 495 158 63 28 13 35 2.6 11 41 87 427 e155 e105 322 135 83 27 31 23 2.3 12 39 78 317 e148 e120 262 122 90 38 44 17 1.9 13 40 72 230 183 e92 259 281 80 24 28 16 1.9 14 40 56 195 270 e90 290 223 72 37 18 14 1.9 15 68 46 173 364 e88 277 157 71 41 16 14 1.9 16 88 68 163 467 e87 269 127 69 17 14 e14 1.9 17 87 59 154 464 e87 325 111 61 21 12 e14 13 18 96 53 181 337 e120 280 118 67 20 18 9.7 14 19 90 52 178 272 129 224 164 70 28 20 8.6 8.4 20 88 40 145 494 117 192 173 81 11 15 7.8 6.3 21 113 73 117 847 122 195 139 71 13 13 7.0 5.4 22 102 302 106 560 113 242 140 56 12 11 6.2 19 23 85 197 106 401 109 212 121 59 21 10 13 34 24 116 131 1190 323 164 181 107 55 7.4 15 3.3 18 25 96 114 1130 e280 166 156 96 107 9.0 20 3.8 22 26 72 87 638 e220 135 140 87 89 15 39 3.6 20 27 55 75 356 e185 113 129 84 74 17 50 3.6 35 28 52 273 295 169 214 121 83 58 13 44 4.2 30 29 37 429 257 e152 --- 118 85 61 11 40 3.7 25 30 42 287 191 e140 --- 117 79 176 9.9 32 3.3 20 31 49 --- 188 138 --- 134 --- 133 --- 31 2.9 --- TOTAL 1974 3193 9368 8978 3249 7468 3786 2428 867.3 650.0 879.4 310.4 MEAN 63.7 106 302 290 116 241 126 78.3 28.9 21.0 28.4 10.3 MAX 116 429 1190 847 214 998 281 176 88 50 242 35 MIN 37 40 106 138 87 107 79 55 7.4 7.8 2.9 1.9 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1949 - 1995, BY WATER YEAR (WY) MEAN 119 161 189 184 200 304 378 202 124 56.6 85.9 73.7 MAX 832 569 527 474 621 699 786 577 492 276 1228 363 (WY) 1956 1956 1974 1949 1981 1953 1987 1989 1972 1972 1955 1975 MIN 16.8 24.6 37.5 15.7 47.9 106 92.9 59.4 28.9 12.1 9.32 10.3 (WY) 1958 1965 1981 1981 1980 1989 1985 1965 1995 1957 1957 1995 SUMMARY STATISTICS FOR 1994 CALENDAR YEAR FOR 1995 WATER YEAR WATER YEARS 1949 - 1995 ANNUAL TOTAL 63694.9 43151.1 ANNUAL MEAN 175 118 172 HIGHEST ANNUAL MEAN 269 1955 LOWEST ANNUAL MEAN 62.0 1965 HIGHEST DAILY MEAN 1190 Dec 24 1190 Dec 24 24800 Aug 19 1955 LOWEST DAILY MEAN 9.9 Sep 13 1.9 Sep 12 .30 Sep 14 1957 ANNUAL SEVEN-DAY MINIMUM 17 Sep 7 2.1 Sep 10 2.1 Sep 10 1995 INSTANTANEOUS PEAK FLOW 2130 Dec 24 a44000 Aug 19 1955 INSTANTANEOUS PEAK STAGE 6.03 Dec 24 b16.48 Aug 19 1955 INSTANTANEOUS LOW FLOW c1.6 Sep 12 .20 Sep 14 1957 10 PERCENT EXCEEDS 434 278 371 50 PERCENT EXCEEDS 115 81 100 90 PERCENT EXCEEDS 28 9.4 22 a From rating curve extended above 5,600 ft3/s on basis of slope-area measurement of peak flow. b From floodmarks. c Also occurred on Sept. 13, 16, and 17. e Estimated