LOCATION.--Lat 38°14'30.3", long 76°30'13.2", St. Marys County, Hydrologic Unit 02070011,
on left bank at downstream side of bridge on State Highway 471 in Great Mills, 0.3 mi downstream
from Western Branch, and 12.0 mi upstream from mouth.
DRAINAGE AREA.--24.0 mi2.
PERIOD OF RECORD.--June 1946 to September 2005, October 2006 to current year.
GAGE.--Water-stage recorder, crest-stage gage and concrete control. Elevation of gage is 10 ft above National
Geodetic Vertical Datum of 1929, from topographic map.
REMARKS.--Occasional regulation by reservoir on Western Branch of St. Marys River, 2.0 mi upstream
since 1975, total capacity, 3,200 acre feet. U.S. Geological Survey satellite data-collection platform
at station. Water-quality records for some prior periods have been collected at this location.
EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 7,950 ft3/s, Aug. 20, 1969,
gage height, 13.34 ft; minimum discharge, 0.13 ft3/s, Aug. 10-14, 1999.
COOPERATION.--Funding for the operation of this station is provided by the Maryland Geological
Survey, and the U.S. Geological Survey.
This station managed by the MD-DE-DC Water Science Center, Baltimore office.