The impacts of fast-paced development, coupled with the loss of forests and continued pollution from urban and agriculture runoff combined to give the Potomac River a D+ in a report by an environmental group.

The 14-year-old Potomac Conservancy said in its first State of the Nation's River report that the Potomac had improved since 1965, when President Lyndon Johnson labeled it a "national disgrace" after centuries of degradation by sewage and other contaminants and made its cleanup a national goal.

The river again supports eagles and osprey along its banks and smallmouth and largemouth bass in its waters.

But in recent years, the improvements have stalled, largely under the weight of added development, said Hedrick Belin, president of the conservancy.

"We feel much improvement is needed, not only for the health of the river itself, but also for the well-being of the Chesapeake Bay," he said.

"We're striving to have a river that is safe for human contact and provides a home for healthy fish that are safe to consume."

In its report, the conservancy notes that the amount of developed land has doubled since the 1970s, especially in the District of Columbia region which is home to 372 million people, or 70 percent of the the watershed's population.

The watershed's population is expected to add another million people over the next two decades, bringing the total to 6.25 million.

"More people means more rooftops and more roads," Belin said. And that, he said, "leads to greater contaminated runoff coming off those hard surfaces."

Indeed, impervious cover-roads, parking lots and roofs-is growing at a faster rate than the population, increasing 50 percent between 1986 and 2000, replacing water-absorbing fields and forests with hard surfaces that accelerate stream-degrading runoff.

Meanwhile, the watershed is losing forests, especially in rapidly developing areas. One concern is that many of those losses have taken place near streams, where they serve as important buffers to protect water quality.

If current trends continue, developed lands in the D.C. area will increase 80 percent between 2000 and 2030, while farms, forests and wetlands decrease by 17.5 percent, according to the conservancy's report.

The river is also plagued by chronic sewer overflows in the D.C. area, where the combined sanitary sewers and storm sewers overflow during heavy rains, spilling untreated sewage into waterways. Although plans are in the works to fix that problem, they are years from completion.

The river suffers from other problems as well, the report notes.

Upstream, increasing concentrations of poultry contribute large amounts of nutrients and other chemicals, including hormones, to waterways.

The Shenandoah River, the largest tributary to the Potomac, has been plagued by a series of large, unexplained fish kills over the last five years.

Also unexplained is the reason for "intersex" fish-males found with eggs-that have been showing up in the river.

There is some good news-the overall amounts of phosphorus, nitrogen and sediment moving down the river is slowly decreasing, though not at a fast enough rate to significantly improve water quality.

To improve the river's grade, the report called for a series of actions:

  • Create more-aggressive programs to protect forest lands, and especially forest streamside buffers.
  • Mandate the use of low-impact development techniques, which promote infiltration of stormwater rather than piping it to streams.
  • Increase state funding to help farmers implement various runoff control practices to reduce pollution.
  • Update the Clean Water Act to include the control of various household chemicals and pharmaceuticals, which are suspected of contributing to intersex fish.

With greater action, the group said there is hope, and Belin said some municipalities are stepping up efforts to deal with the effects of runoff. He noted that Maryland's Montgomery County recently approved new rules that call for more aggressive actions to control runoff when roads are built, or rebuilt.

Belin said the river received a D+ because the goal is for it to be safe for fishing and swimming 365 days a year, and measured against that standard, it was less than average.

He noted that the participants in a triathlon that took place this fall were told to check their e-mail the morning of the event, because the swimming portion of the contest took place in a section of the river near Theodore Roosevelt Island. In the event of rain before the swim, organizers expected they would have to convert the race to a biathlon because of water pollution.

"That illustrates why I don't think the water quality is above average right now," Belin said. "If we're that close to the edge where if it rains, we don't want you going in because bad things are going to happen, that's below average."