Click
to
hide
Water-Year
Summary
instructions
and
information
- Water-Year Summary reports summarize a year of hydrologic data in a printer-friendly format.
- For water years 2014 onward, choose a water year and parameter and an on-demand Water-Year Summary report will be generated.
- For water years 2006 through 2013, choose a water year and an Annual Water Data Report will be provided.
- For water years 2005 and earlier, Annual Water Data Reports may be available in digital format.
- Not all sites have reports available for every water year.
USGS Water-Year Summary 2024
01087000 BLACKWATER RIVER NEAR WEBSTER, NH
LOCATION - Lat 43°17'49", long 71°41'42" referenced to North American Datum of 1927, Merrimack County, NH, Hydrologic Unit 01070003, on left bank, 0.2 mi west of Clothspin Bridge Road and Pleasant Street intersection at Dingit Corner, 0.4 mi downstream from Clothspin Bridge Road, 2.4 mi downstream from Blackwater Dam, 2.5 mi southeast of Davisville Road (NH 127) and Long Street intersection in Webster, 4.4 mi west of Main Street (US 3S) and King Street (US 4E) intersection in Boscawen, and 6.6 mi upstream from mouth at Contoocook River.
DRAINAGE AREA - 129 mi².
REVISIONS HISTORY - WSP 696: Drainage area. WSP 821: 1936(M). WSP: 851: 1936. WSP 867: 1936 (flood-report data). WSP 1231: 1919-20, 1927, 1928(M), 1929-32, 1933-34(M), 1936 (calendar-year summaries).
SURFACE-WATER RECORDS
PERIOD OF RECORD - Discharge records: May 1918 to September 1920, February 1927 to September 1989. Published as "near Contoocook", 1918-20, 1927-35. Records published under both names October 1934 to September 1935.
Partial-record station: October 1989 to current year.
Peak Streamflow: Water years 1919, 1920, 1927 to 2016.
Miscellaneous Discharge measurements: Water years 1990 to current year.
GAGE - Water-stage recorder. Elevation of gage is 431.17 ft above North American Vertical Datum of 1988.
COOPERATION - U.S. Army Corps of Engineers, New England District.
REMARKS - Satellite gage-height telemeter at station.
EXTREMES FOR PERIOD OF RECORD - Maximum discharge, 11,000 ft³/s, March 19, 1936, gage height, 11.78 ft, from floodmarks, from rating curve extended above 6,700 ft³/s on basis of slope-area and critical-depth measurements of peak flow. Maximum discharge since construction of Blackwater Reservoir in 1941, 2,390 ft³/s, April 16, 1951, April 10, 1952, gage height, 7.18 ft. Maximum stage since at least 1733, that of March 19, 1936.
WATER-QUALITY RECORDS
PERIOD OF RECORD - Water-Quality Field/Lab samples: Water years 1957, 1975 to 1999.
