This report presents groundwater withdrawal data from 1900 through 1980 for Maryland counties lying with the Coastal Plain physiographic province, as well as a summary section for the total Maryland Coastal Plain. The types of water use included are domestic, military, water supplier, industrial/commercial, and irrigation. The data were obtained from state and county reports, biannual pumpage reports submitted to the Maryland Water Resources Administration, communication with individual owners, and estimates based on existing published data. The amount of groundwater withdrawn from aquifers in the Maryland Coastal Plain in 1900 was approximately 26 million gallons per day (Mgal/d) compared to nearly 134 Mgal/d in 1980. Jurisdictions withdrawing more than 10 Mgal/d for most of the 80-year period were Anne Arundel and Baltimore Counties and Baltimore City. The greatest withdrawals for most of the early part of the period were for domestic and industrial/commercial uses; however, water-supplier use dominated after 1965. Groundwater use for irrigation became important in the Coastal Plain around 1960 and increased steadily from approximately 2 Mgal/d in 1960 to nearly 12 Mgal/d in 1980. (USGS)