USGS Water-Year Summary 2024
381110076550501 55P 5
Northern Atlantic Coastal Plain aquifer system
Patapsco Formation
LOCATION - Lat 38°11'10", long 76°55'05" referenced to North American Datum of 1927, Westmoreland County, VA, Hydrologic Unit 02070011, behind craft shop at George Washington Birthplace National Monument, 3.8 mi southeast of Colonial Beach. Owner: National Park Service.
GROUNDWATER RECORDS
WELL CHARACTERISTICS - Depth 471 ft. Upper casing diameter 6 in; top of first opening 451 ft, bottom of last opening 466 ft. Drilled observation water well, screened 451 to 466 ft.
DATUM - Land-surface datum is 24 ft above National Geodetic Vertical Datum of 1929. Measuring point: TOP OF RECORDER SHELF, 3.0 ft above land-surface datum, Jun. 24, 1974 to present.
PERIOD OF RECORD - June 1974 to current year.
GAGE - Electronic data logger, 15-minute record interval. Apr. 24, 1979 to Nov. 2, 1999, digital recorder, 60-minute record interval. Prior to Apr. 24, 1979, continuous strip-chart recorder.
EXTREMES FOR PERIOD OF RECORD - Highest water level measured, 25.05 ft below land-surface datum, June 24, 1974; lowest recorded, 80.17 ft below land-surface datum, December 29, 2022.