The Potomac River’s future presents “a troubling picture,” concludes the sixth annual report of the Potomac Conservancy.
“Too many stretches...are still too polluted to allow you to safely swim, boat, or fish, or to support healthy populations of fish and other aquatic life,” the study proclaims.
Titled “Troubled Waters,” the report targets non-point pollution as the “root cause” of the degradation along 51 percent of impaired steams miles, while agricultural practices contribute 37 percent. Unlike “point source” pollution discharged from a discrete site like a pipe, non-point pollution is diffuse and often carried in stormwater washing off impervious surfaces like roofs, parking lots and roads.
The 405-mile Potomac River provides drinking water to more than 5 million people in the Washington area.
In releasing the study, conservancy President Hedrick Belin remarked, “Unless we develop and redevelop differently — using proven technology and techniques to capture rainwater where it falls — we will see our rivers become more polluted over the next 40 years. This is because of continued population growth and the associated increase in hardened surfaces that create polluted runoff when it rains.”
Conservancy officials predict the Washington region will add 2 million people, a number equivalent to the population of Houston, Texas, in the next 20 years.
The report credits the 1972 federal Clean Water Act with making the river healthier, but highlights some “worrying statistics” about Virginia’s portion of the upper Potomac basin:
- Over half of the 2,500 stream miles designed for
recreational use are impaired because of bacterial pollution;
- Almost one third of 3,000 stream miles designated
for aquatic life failed because of high sediment loads; and
- Around half of the 600 stream miles designated for
fish consumption were “too polluted with chemicals” to produce fish safe to eat.
The conservancy targets four pollutants, labeled its “most wanted” list:
- excess phosphorus from farms, yards and sewage
- pathogens or bacterial pollutants from fecal
matter coming from failing septic systems, old sewer systems, livestock, domestic pets and wild animals;
- sediment washing into the river from construction, farm
fields, river banks and logging operations, exacerbated by removing streambank vegetation; and
- chemicals from 750,000 tons of road salt used on
highways each year; PCBs, toxic metals like mercury, cadmium and arsenic; and pesticides, herbicides, pharmaceuticals and others known as potential endocrine disrupters.
Stating that “we know what we need to do to reduce the harm,” the Conservancy offers several recommendations, most focused on curbing stormwater runoff. The group advocates enacting stronger “green”
stream buffer requirements, requiring pollution reduction in stormwater permits and showing urban and suburban homeowners and businesses how to reduce impervious surfaces.
In 2011, the conservancy downgraded the river to a D grade from a D+ in 2007. American Rivers in May labeled the Potomac the nation’s “most endangered river.”