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Claire A. Richardson

Publications and source records attributed to Claire A. Richardson.

4 recordsLinked to original sources
USGS1977

Availability of ground water in Montgomery County, Maryland

Montgomery County, Md., is underlain by consolidated rocks that, on the basis of well yields, have been subdivided into six hydrogeologic units. The distribution of the hydrogeologic units are shown on a map (scale 1:62,500). Most wells drilled in the county yield between 6 and 25 gal/min (0.4 to 1.6 L/s); however, about one-third of the wells drilled in the most productive hydrogeologic unit yielded more than 25 gal/min (1.6 L/s). Water from all units is suitable for domestic, public supply, and most industrial uses, but may require treatment for the removal of iron and hardness.

Open-File Report↗
USGS1958

Limestone aquifers of Maryland

Limestone rocks are an important source of ground water in the Piedmont and Appalachian areas of Maryland. The major limestone aquifers are the Cockeysville and Wakefield marbles and the Silver Run, Tomstown, Frederick, Grove, Waynesboro, Elbrook, Conococheague, Beekmantown, Stones River, Tonoloway, Helderberg and Greenbrier formations. Drilled and dug wells and springs are common sources of water supply in the limestone areas. The depths of 298 limestone wells range from 8.7 to 1,800 feet and average about 150 feet. The yields of these wells range from 0.1 to 575 gpm. Specific capacities, or yield per foot of drawdown, range in 137 wells from 0.1 to 43 gpm per foot. Springs are common in the limestone areas and their flow varies widely at different times. Most of the known springs are of the 5th magnitude or lower, and therefore have a mean flow of less than 100 gpm. The quality of water from the limestone aquifers is satisfactory for most purposes, but is commonly hard and slightly alkaline. The limestone aquifers are large essentially untapped ground-water reservoirs whose hydrologic character is only partially understood.

Maryland↗