USGS - science for a changing world

Water Science for Maryland, Delaware and the District of Columbia

Home >> Publications >> Press Release

Water conditions begin to decline in Maryland, Delaware, and D.C. - Streamflow and Groundwater Levels Decreased During May

U.S. Department of the Interior
U.S. Geological Survey

Wendy McPherson (
Maryland-Delaware-D.C. Water Science Center
5522 Research Park Drive
Baltimore, MD 21228
FAX: (443)498-5510

Jump to archives >>

Updated: June 6 , 2000

Below-normal precipitation in May (24 percent below average at BWI airport) in combination with seasonal increases in evapotranspiration resulted in lower Groundwater levels and decreased streamflow in the Maryland-Delaware-D.C. region, according to hydrologists at the U.S. Geological Survey (USGS) in Baltimore, Maryland. Some of the largest decreases of streamflow for May were at the Potomac River near Washington, D.C., where streamflow averaged 4.7 billion gallons per day, which is about 49 percent of normal for May and only 44 percent of the streamflow in April.

The average streamflow into the Chesapeake Bay during May 2000 was 53.8 billion gallons per day, which is a 44-percent decrease from April and 14 percent below the long-term average for May. In western Maryland and on the upper Potomac River, streamflow was in the deficient range for the month of May and decreased to half the long-term average for May. Streamflows on the Eastern Shore in May were much lower than those measured in April, but were still normal for this time of year. Throughout the rest of the bistate area, streamflow in local streams decreased, but remained within the normal range for May.

Groundwater levels at the end of May decreased throughout the area but generally remained in the normal range throughout the entire bistate area. Monthly updates of Groundwater conditions for 32 key observation wells located throughout Maryland and Delaware may be found at Water storage in the Baltimore reservoir system was 80.8 billion gallons near the end of May, which is 100 percent of average and 18 percent above last year at this time.

As the nation's largest water, earth and biological science, and civilian mapping agency, the USGS works in cooperation with more than 2,000 organizations across the country to provide reliable, impartial scientific information to resource managers, planners, and other customers. This information is gathered in every state by USGS scientists to minimize the loss of life and property from natural disasters, contribute to the sound conservation and the economic and physical development of the nation's natural resources, and enhance the quality of life by monitoring water, biological, energy, and mineral resources.

** * USGS * * *

In-depth information about USGS programs may be found on the USGS home page at and for Chesapeake Bay activities.

Archived News Releases 2000-Present








Accessibility FOIA Privacy Policies and Notices

Take Pride in America logo logo U.S. Department of the Interior | U.S. Geological Survey
Page Contact Information:
Page Last Modified: Thursday, September 14, 2017