Maryland Department of Natural Resources


Water level declines in the Magothy aquifer in southern Maryland related to increases in pumpage

1983, Mack, F.K., Wheeler, J.C., and Curtin, S.E.

USGS Open-File Report 82-919


Water levels in the Magothy aquifer in southern Maryland have declined in response to increases in pumping.

Distinct and extensive cones of depression have developed in two places: (1) localities surrounding the electric power generation plant at Chalk Point in southeastern Prince George's County, and (2) the rapidly developing Waldorf area of northern Charles County.

Pumpage from the Magothy aquifer, in the project area, increased from 0.4-5 million gallons per day (Mgal/d) in 1962 to about 3.3 Mgal/d in 1980. Water-level declines of as much as 60 feet have been measured in observation wells more than 1 mile from production wells. Hydrographs of daily values for water levels and pumpage data show several examples of the close relationship between pumpage and water levels. One hydrograph based on daily values shows that water levels rose 1 foot in an observation well as a result of the temporary termination of pumping 0.25 Mgal/d from a production well located 2 1/2 miles away.

Earliest measured water levels indicate the prepumping potentiometric surface was about 50 feet above sea level in the Waldorf area and 30 feet above sea level in the Chalk Point area.

Pumpage from the Magothy in the Chalk Point area began in 1963 and stabilized at approximately 0.8 Mgal/d by 1975. Water levels declined as much as 61 feet by 1980.

Pumpage from the Magothy aquifer in the Waldorf area began in 1948 and increased uniformly to 2 Mgal/d by 1980. Water levels declined 85 feet in parts of the area during that period.

Downloads and Data

USGS Open-File Report 82-919 (pdf, 14 MB)

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