PAWCATUCK RIVER BASIN 01118500 PAWCATUCK RIVER AT WESTERLY, R.I. (National Stream-Quality Accounting Network Station) LOCATION.--Lat 41o23'01", long 71o50'01", Washington County, Hydrologic Unit 01090005, on left bank at Westerly, 2.1 mi downstream from Shunock River. DRAINAGE AREA.--295 mi2. WATER-DISCHARGE RECORDS PERIOD OF RECORD.--November 1940 to current year. REVISED RECORDS.--WSP 1051: Drainage area. GAGE.--Water-stage recorder. Datum of gage is 1.76 ft below sea level. REMARKS.--Records good. Diurnal fluctuation at low flow prior to 1962 by mills upstream; regulation much greater prior to 1958. Diversion upstream for municipal supply of Westerly. EXTREMES OUTSIDE PERIOD OF RECORD.--Flood in March 1936 reached a discharge of 3,150 ft3/s, by computation of flow over dam 1.5 mi upstream. Maximum discharge since 1886 occurred in November 1927 and was possibly more than twice that in March 1936. Maximum stage since at least 1635, 15.0 ft Sept. 21, 1938, due to hurricane tidal wave. 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 1 144 92 553 739 547 1090 506 621 503 209 91 49 2 129 129 461 882 545 1100 484 777 429 203 85 48 3 126 126 399 918 526 980 469 775 403 201 84 49 4 121 126 359 853 541 875 462 702 412 186 90 48 5 119 137 400 761 673 795 448 627 396 182 119 45 6 114 139 618 680 644 736 432 576 365 170 148 45 7 114 140 672 768 601 704 424 531 407 164 185 47 8 111 133 600 1020 529 686 434 490 518 159 164 48 9 111 132 522 1030 500 784 486 462 511 153 139 49 10 107 158 474 912 477 908 600 449 477 150 116 49 11 108 181 577 805 476 874 648 511 419 148 105 49 12 105 183 644 758 480 799 610 739 414 148 100 49 13 107 179 578 768 457 734 656 746 477 145 92 48 14 112 175 506 777 429 695 746 667 523 145 90 49 15 119 172 476 769 414 654 717 608 511 137 84 52 16 117 170 448 764 801 628 647 595 454 134 80 54 17 102 160 424 778 1050 608 585 577 397 129 77 73 18 92 150 455 746 958 706 523 627 355 173 76 147 19 94 311 472 688 844 739 571 640 321 197 70 129 20 86 468 447 740 757 688 790 653 298 168 66 106 21 90 414 417 1020 702 671 836 617 276 148 65 95 22 86 380 400 1060 667 780 800 554 254 139 61 86 23 84 348 395 1000 627 829 776 501 240 132 59 92 24 97 312 905 930 634 765 717 464 230 127 57 94 25 98 280 1500 850 707 693 643 440 279 117 55 75 26 94 254 1490 771 683 638 586 431 317 114 53 82 27 90 237 1300 710 624 599 550 420 290 109 53 96 28 90 409 1110 653 704 574 515 394 258 108 54 94 29 90 635 974 605 --- 550 509 397 234 103 54 88 30 90 626 836 565 --- 530 513 515 221 101 49 76 31 90 --- 717 541 --- 524 --- 561 --- 97 48 --- TOTAL 3237 7356 20129 24861 17597 22936 17683 17667 11189 4596 2669 2111 MEAN 104 245 649 802 628 740 589 570 373 148 86.1 70.4 MAX 144 635 1500 1060 1050 1100 836 777 523 209 185 147 MIN 84 92 359 541 414 524 424 394 221 97 48 45 CFSM .35 .83 2.20 2.72 2.13 2.51 2.00 1.93 1.26 .50 .29 .24 IN. .41 .93 2.54 3.14 2.22 2.89 2.23 2.23 1.41 .58 .34 .27 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1941 - 1995, BY WATER YEAR (WY) MEAN 258 455 665 750 806 1039 975 709 495 263 237 219 MAX 1186 1450 1789 2151 1377 1775 2603 1274 2246 642 763 1233 (WY) 1956 1956 1987 1979 1982 1994 1983 1948 1982 1959 1946 1954 MIN 87.2 93.2 115 131 325 495 371 325 210 98.5 81.7 65.7 (WY) 1950 1966 1966 1981 1980 1981 1966 1986 1942 1957 1964 1964 SUMMARY STATISTICS FOR 1994 CALENDAR YEAR FOR 1995 WATER YEAR WATER YEARS 1941 - 1995 ANNUAL TOTAL 190437 152031 ANNUAL MEAN 522 417 575 HIGHEST ANNUAL MEAN 871 1973 LOWEST ANNUAL MEAN 251 1981 HIGHEST DAILY MEAN 3350 Mar 11 1500 Dec 25 6220 Jun 6 1982 LOWEST DAILY MEAN 84 Oct 23 45 Sep 5 25 Aug 17 1941 ANNUAL SEVEN-DAY MINIMUM 90 Oct 18 47 Sep 2 47 Sep 2 1995 INSTANTANEOUS PEAK FLOW 1550 Dec 25 7070 Jun 6 1982 INSTANTANEOUS PEAK STAGE 6.34 Dec 25 12.86 Jun 6 1982 INSTANTANEOUS LOW FLOW 47 Sep 2 ANNUAL RUNOFF (CFSM) 1.77 1.41 1.95 ANNUAL RUNOFF (INCHES) 24.01 19.17 26.46 10 PERCENT EXCEEDS 1190 782 1190 50 PERCENT EXCEEDS 395 424 450 90 PERCENT EXCEEDS 105 83 127