by Kate Diffenderfer.(Diffenderfer is the program assistant for the Maryland Coastal Bays Program.)

To accommodate the steadily increasing population growth within the coastal bays watershed, many acres of uplands, wetlands, forests, and farmland have been cleared to make way for more residential and commercial use. With this increase in development and population growth, a very important question
arises. “Will there be enough contaminant-free groundwater to adequately serve the citizens of Worcester County?”

The only source of drinking water, the primary source of irrigation water and the major source of freshwater to the coastal bays is groundwater. The risk of groundwater contamination by nutrients is high due to the watershed’s sandy soils, high water table, and relatively unconfined layers of groundwater.

High levels of certain nutrients (e.g. nitrate) in the groundwater we drink can have serious human health impacts as well as contribute to eutrophication within the bays. Common sources of nitrate contamination
include fertilizers, animal wastes, septic tanks, municipal sewage treatment systems and runoff from impervious surfaces. Although human ingestion of low levels of nitrates occurs naturally through certain foods we consume, scientists believe that long-term ingestion of water high in nitrates increases the risk of certain types of cancer.

A 1999 report conducted by the United States Geological Survey (USGS) examined the estimated total groundwater discharge and potential nitrate loads into Maryland’s coastal bays--Assawoman, Isle of Wight, Chincoteague, Newport and Sinepuxent. Potential nitrate loadings into the coastal bays from groundwater were estimated to be 272,000 pounds per year from direct groundwater discharge, and 862,000 pounds per year from stream base flow.

Another impact from increasing development and groundwater consumption is saltwater intrusion. Saltwater intrusion occurs when too much water is pumped from aquifers (permeable underground rocks, soil, or gravel which holds freshwater that yields supplies of water to wells, springs, and estuaries). In a separate study, the USGS, along with the Maryland Geologic Survey and other agencies, are currently investigating the possibility of saltwater intrusion in rapidly developing areas along the Atlantic Ocean, such as Ocean City. These studies will map the present distribution of saltwater, develop models to predict future conditions, and establish a monitoring program to observe water level and water-quality trends.

Small steps residents can take, such as installing low-flow showerheads, low-flush toilets or turning the tap off when shaving, brushing teeth, or washing dishes can make a difference. Showering instead of bathing saves 20-30 gallons of water, and watering the lawn once a week rather than every day can save hundreds.

In order to meet the environmental, economic, and recreational needs of our present population without compromising the needs of future generations, county residents must be well informed on issues and must be ready to make decisions concerning the future of their watershed. Such decisions are not
always easy but recognizing that economic prosperity depends on the health of the environment is a critical first step.

For information on how to conserve groundwater, contact the Maryland Coastal Bays Program office at (410) 213-2297.

For a copy of the USGS report, contact: District Chief, U.S. Geologic Survey, 8987 Yellow Brick Road, Baltimore, MD 21237.