Potentiometric Surface of the Upper Patapsco Aquifer in Southern Maryland, September 2001

This report presents a map showing the potentiometric surface of the Upper Patapsco aquifer in the Patapsco Formation of Cretaceous age in Southern Maryland during September 2001. The map is based on water-level measurements in 49 wells. The potentiometric surface was highest at 118 feet above sea level near the northern boundary and outcrop area of the aquifer in northern Anne Arundel County. From this area, the potentiometric surface declined to the southeast toward large well fields in the Annapolis area, and from all directions toward a cone of depression located southwest of Waldorf. The ground-water level declined to 26 feet below sea level in the Annapolis area, and the lowest water level was 132 feet below sea level southwest of Waldorf.