The difference between the potentiometric surfaces of the Aquia aquifer, September 1982 and September 1999 in southern Maryland

This report presents a map showing the change in the potentiometric surface of the Aquia aquifer in the Aquia Formation of Paleocene age in Southern Maryland for September 1982 and September 1999. The map, based on water level measurements in 67 wells, shows that the change of the potentiometric surface during the 17-year period declined from zero in the northernmost part of the study area, which is the outcrop of the aquifer, to 101 feet at Lexington Park. Lexington Park is near the southeasternmost part of the study area and approaches the downdip boundary of the aquifer.