The Difference Between the Potentiometric Surfaces of the Aquia Aquifer in Southern Maryland, September 1982 and September 2009

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 between September 1982 and September 2009. The map, based on water level differences obtained from 49 wells, shows that the potentiometric surface during the 27-year period declined from zero in the northernmost part of the study area, which is the outcrop of the aquifer, to 111 feet at Lexington Park. Lexington Park is near the southeasternmost part of the study area and approaches the downdip boundary of the aquifer. The map also shows well yield in gallons per day for 2008 at wells or well fields.