Maryland Department of Natural Resources

Power Plant Observation-Well Network

Groundwater is the principal source of freshwater supply in most of Southern Maryland and adjacent Eastern Shore. It is also the source of freshwater supply used in the operation of the Calvert Cliffs, Chalk Point, and Morgantown power plants. Increased groundwater withdrawals over the last several decades have caused groundwater levels to decline. The Maryland Geological Survey (MGS) and the U.S. Geological Survey (USGS) have maintained a groundwater level monitoring network started in the 1940s to observe changes in groundwater levels through time. Groundwater-level monitoring has been especially critical for Southern Maryland and adjacent Eastern Shore where groundwater is the primary source of water supply. Many observation wells were added to the network in the early 1970s following the establishment of the Power Plant Research Program (PPRP) of the Maryland Department of Natural Resources in order to monitor groundwater levels at Maryland power plants. Water-level data collected from the monitoring network and water-withdrawal data from the confined aquifers which supply water for the operation of Maryland’s power plants are used by the PPRP to evaluate potential impacts of Maryland’s power plants on groundwater resources.

Aquifers pumped by power plants in Maryland are as follows:

Calvert Cliffs: Aquia; Chalk Point: Magothy, Upper Patapsco, and Patuxent; Morgantown: Lower Patapsco; Panda: Lower Patapsco; Perryman: Surficial; SMECO: Upper Patapsco; and Vienna: Surficial

Potentiometric surface and difference maps are generated every two years and published by the Maryland Geological Survey and the U.S. Geological Survey for the confined aquifers (Aquia, Magothy, Upper and Lower Patapsco, and Patuxent)