Overall, the Potomac remains an astounding story of revitalization. In 1965, after centuries of contamination by raw sewage and industrial pollutants, President Lyndon B. Johnson (D) called it a “national disgrace.”But now that progress has been stunted by two parallel factors: the ever-outwards growth of suburbia, and the development of large, industrial poultry farms in the Shenandoah Valley. Suburbia removes trees and replaces groundcover with non-permeable surfaces, causing rainwater to carry whatever pollutants are around with it into the river. A strong combination of trees and native plants around the Potomac's tributaries is key to the maintenance of the river.
Since then, there have been large-scale improvements at wastewater treatment plants, and the Potomac is now clean enough to support numerous bald eagles and a famous stock of smallmouth and largemouth bass. - LoudounExtra
(Loudoun's watersheds, courtesy of the Loudoun County Website)
But the problem is not solely that of suburban sprawl.
Upstream, in such places as Virginia’s Shenandoah River valley, manure from large chicken farms and other agriculture washes downstream to the Potomac, carrying bacteria and pollutants that feed huge algae blooms. - LoudounExtraAgriculture is key to the economy of Virginia and the economy of the Valley, but the Potomac is critical to the very health and well being of the Washington metropolitan area. There must be joint management of the needs of people and agriculture when it comes to the Potomac, lest we suffer the rancor and recrimination so common in Western water disputes.
With proper planning and development (LEED construction would help) we can mitigate the worst effects of development and large-scale agriculture. Localities must take steps to include watershed health into account when considering development, and do what they can to make sure that the flora placed near streams and creeks is helping the health of those critical waterways. And such measures must be considered all along the length of the Potomac watershed.
The most difficult task will be accommodating the agricultural needs of the Valley with the consumption quality needs of the DC suburbs, but with patience, understanding, and most importantly, advanced planning, Americans should be able to come together to preserve a critical resource which we have saved once before.
(For folks not in the area, check out this great tool: Interactive Watersheds, which allows you to explore watersheds throughout the U.S.)