Water Use

Groundwater is the primary source of freshwater for about 1.5 million people in Maryland's Coastal Plain. The Coastal Plain aquifer system is the sole source of drinking water for most of Southern Maryland and nearly all of the Eastern Shore; it is also an important water supply for the counties northeast of Baltimore, along the western shore of Chesapeake Bay. The Coastal Plain aquifer system extends into neighboring states and is extensively used as a source of freshwater supply in Delaware, New Jersey, and Virginia.

Groundwater withdrawals in the Maryland Coastal Plain increased about 32 percent between 1980 and 2005, with withdrawals by public-water suppliers increasing nearly 34 percent and irrigation withdrawals increasing over 100 percent (Soeder and others, 2007). Long-term water-level measurements commonly show significant declines over several decades, which are attributed to groundwater withdrawals. The Maryland Department of the Environment (MDE), Water Supply Program has regulatory authority to manage water resources within the State.

Water-use data, which consists of water withdrawals, return flows, and consumptive use, are an integral part of the groundwater budget, and provide necessary information for determining current and future stress on groundwater and surface-water systems, and indicate sufficiency of supply to meet present and future water needs for residential, commercial, industrial, and agricultural purposes. Data on historical water withdrawals are necessary for the construction of the regional groundwater-flow model. Those data will be compiled from existing Maryland Department of the Environment databases.