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LOCATION.--Lat 39°14'17.7", long 77°03'20.6", Montgomery County, MD, Hydrologic Unit 02060006, on right
   bank at downstream side of bridge on State Highway 97, 0.6 mi upstream from Cattail Creek, 0.8 mi
   upstream from Triadelphia Reservoir, 1.1 mi northeast of Unity, and 97 mi upstream from mouth.
DRAINAGE AREA.--34.8 mi2.
PERIOD OF RECORD.--July 1944 to current year.
REVISIONS HISTORY--WSP 1111: 1947. WSP 1432: 1948. https://waterdata.usgs.gov/nwis/dv/?site_no=01591000: 2013.
GAGE.--Water stage recorder, crest-stage gage and concrete control. Datum of gage is 364.04 ft above 
   North American Vertical Datum of 1988. Prior to Aug. 14, 1946, non-recording gage at same site and gage datum.
REMARKS.--U.S. Geological Survey satellite data-collection platform at station.
EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 21,800 ft3/s, Sept. 11, 1971, gage height, 18.60 ft;
   minimum discharge, 0.20 ft3/s, Sept. 10-12, 1966.
COOPERATION.--Funding for the operation of this station is provided by the Washington Suburban Sanitary
   Commission, and the U.S. Geological Survey.
Boating safety tips
This station managed by the MD-DE-DC Water Science Center Baltimore office.

Available Parameters Available Period
1985-10-03  2021-09-25
2007-10-01  2021-09-25


  -- or --



Summary of all available data for this site
Instantaneous-data availability statement

Discharge, cubic feet per second

Most recent instantaneous value: 58.1 09-25-2021   04:55 EDT
Graph of  Discharge, cubic feet per second

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Daily discharge, cubic feet per second -- statistics for Sep 25 based on 77 water years of record more
Median 75th
Mean Most Recent
Value Sep 25
1.77 7.8 13 20 28 58.1 730

Gage height, feet

Most recent instantaneous value: 2.50 09-25-2021   04:55 EDT
Graph of  Gage height, feet

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