A local non-profit is warning that rapid development is squeezing out forested land. This in turn is influencing the quality of water in the Potomac River, where the D.C. region draws approximately 90 percent of its drinking water.
Forests act like a sponge -- they absorb rainfall and produce very little runoff. This compared to paved, or developed surfaces, which carry pollutants including pesticides and insecticides into the river. Slightly more than half of the land in the Potomac River basin is forested, which is less than what is needed for high water quality. Hedrick Belin, the President of the Potomac Conservancy, says the health of the Potomac depends on the health of the forests.
"This summer Trump National Golf Course in Loudon County cut down 450 trees. Today 1.5 miles of shoreline is without trees," Belin says.
Belin also says agriculture is still a leading source of pollution. He wants more support for farmers so they can change how they dispose of manure, build fences to keep cattle out of streams and build forested buffers around streams.