The difference between the potentiometric surfaces of the lower Patapsco Aquifer, September 1990 and September 1997 in southern Maryland

This report presents a map that shows the change in the potentiometric surface of the Lower Patapsco aquifer in the Lower Patapsco Formation of Cretaceous age in Southern Maryland for September 1990 and September 1997. The map, based on water-level measurements in 53 wells, shows that the change of the potentiometric surface during the 7-year period ranged from rises of 8 feet at Indian Head and 1 foot near the outcrop area in Glen Burnie to declines of 39 feet at Arnold, 37 feet at Waldorf, and 37 feet at Morgantown.