USGS Water-Year Summary 2024
393158076302601 HA Ca 23
Piedmont and Blue Ridge crystalline-rock aquifers
Loch Raven Schist
LOCATION - Lat 39°31'59.36", long 76°30'24.60" referenced to North American Datum of 1983, Harford County, MD, Hydrologic Unit 02060003, at Gunpowder State Park, Hess.
GROUNDWATER RECORDS
WELL CHARACTERISTICS - Depth 200 ft. Upper casing diameter 6 in; top of first opening 23 ft, bottom of last opening 200 ft. Drilled, observation, water-table well; open hole below 23 ft.
DATUM - Land-surface datum is 473.57 ft above North American Vertical Datum of 1988. Measuring point: Top of casing, 1.6 ft above land-surface datum, Jul. 1, 1974 to Sep. 19, 2009; Top of recorder shelter platform, 1.68 ft above land-surface datum, Sep. 18, 2009 to present.
PERIOD OF RECORD - July 1974 to current year.
GAGE - Water level measurements by U.S. Geological Survey personnel. Equipped with graphic water-level recorder from July 1974 to September 1976 and digital water-level recorder from October 2009 to October 2012. Discrete Water Level Measurements from June 1974 to Present.
EXTREMES FOR PERIOD OF RECORD - Highest water level measured, 3.59 ft below land surface, September 27, 1975; lowest measured, 10.50 ft below land surface, September 25, 2002.