Pollution Rising In Tributaries of Bay, Data Show
Scientists Cite Suburbs' Growth As a Likely Cause of Backslide

By David A. Fahrenthold
Washington Post Staff Writer
Wednesday, December 5, 2007

The massive government effort to clean up the Chesapeake Bay is not just falling short of its goals. Now the bay's pollution might actually be taking a turn for the worse.

New federal research indicates that pollution has crept up in some of the Chesapeake's biggest tributaries this decade, after a slow decline during the 1980s and 1990s. In the Potomac, the Patuxent and other major rivers, the pollutants on the rise include those blamed for low-oxygen "dead zones."

One likely cause for the apparent backslide, scientists say, is suburban development across the bay's watershed. As houses and parking lots replace farms and forests, they say, the result is a new glut of polluted runoff.

The leaders of the Chesapeake cleanup, including the governors of Virginia and Maryland and the mayor of Washington, will hold their annual Chesapeake Executive Council meeting today in Annapolis.

They were supposed to be making environmental history by now, delivering a healthy bay by a 2010 deadline. Instead, the leaders face the danger that the Chesapeake's modest progress might be rolled back.

"Growth in the watershed is starting to overwhelm our restoration efforts," said Frank Dawson, an assistant secretary at Maryland's Department of Natural Resources. Probably because of that growth, Dawson said, "there are certain areas in the bay where we are starting to go back in the wrong direction."

The day-to-day coordinator of the cleanup effort, Environmental Protection Agency official Jeffrey L. Lape, said the increases in pollution are not a sign of failure.

Lape, who is director of the EPA's Chesapeake Bay Program Office, said the new research "just simply [suggests] that the existing actions aren't adequate to keep up with the new sources" of pollution.

The research, published last month by the U.S. Geological Survey, charts the levels of two critical bay pollutants: nitrogen and phosphorus. These two chemicals, found in manure, lawn fertilizer and treated sewage, help fuel the large algae blooms that create dead zones in the bay.

The scientists used equations to remove variations caused by high or low rainfall. They were aiming to isolate the human pollution signature: Were people getting better or worse at keeping these contaminants out of the water?

In many tributaries, the answer was better -- for a while. For instance, measurements taken at Chain Bridge, which connects the District and Virginia, showed that phosphorus levels in the Potomac fell more than 20 percent between 1984 and 1995. In the Patuxent, measured at Bowie, nitrogen fell more than 60 percent between 1984 and 2000.

These declines happened after the first Chesapeake Bay Agreement in 1983, when local and state governments pledged to help the estuary. In the 1980s and 1990s, detergents were purged of a high-phosphorus ingredient, and sewage plants took the first steps to clean up their effluent.

But then, starting in the late 1990s, the graphs start to show a change.

In some rivers, the research shows, the long decline tailed off during that period, and pollution levels flat-lined. Then, in some cases, the contamination started going up again. The researchers looked closely at nine of the biggest rivers that feed the bay. Eight of them showed an uptick in one pollutant or the other, and four showed increases in both.

Some increases were slight: In the Patuxent, for example, the nitrogen level rose just a few percent between 2000 and 2006. But other examples were more troubling: In the James River, near Richmond, all of the decline in phosphorus appeared to be erased.

The Potomac experienced one of the most dramatic reversals. After its 20 percent drop, the level of phosphorus started increasing, until it was nearly 20 percent higher than where it had started in 1984.

Geological Survey scientists said this week that their calculations might have caused some of the upswings to appear more pronounced than they really are.

"We need to be able to look at the last five years in more detail" to determine whether the increases are real, researcher Scott Phillips said.

Also, he noted, the news is not all bad: In many cases, pollutant levels are still far below their 1984 levels.

Still, some bay scientists said the apparent upswings were worrisome.

"If I were making investments, my own personal money, and if I had one that looked like that" -- with a reversal of course in the last few years -- "I'd be pretty curious," said Donald F. Boesch, president of the University of Maryland's Center for Environmental Science. "Rather than looking just at my average return of the 20-year period."

Scientists and environmentalists said the most likely cause of the upswings is urban and suburban development. One recent federal report found that 170,000 people were moving to the Chesapeake watershed every year.

Environmentalists say more people means more concrete, which doesn't allow rainwater to seep naturally through roots and soil. Instead, it becomes polluted runoff, carrying nitrogen, phosphorus and other pollutants into bay tributaries.

"The treadmill is going faster and faster, and we're having to run faster just to stay even," said William C. Baker, the president of the Chesapeake Bay Foundation. On Monday, his group gave the bay's health a score of 28 out of 100, down one point from last year.

Yesterday, the District announced some apparent good news for the bay. Because of an agreement with the EPA, city officials said they would plant 13,500 trees and replace some sidewalks and road medians with green space. Those moves, among others, are intended to provide a natural filter for runoff headed toward the Potomac and Anacostia rivers, both bay tributaries.

"It's a huge turning point for the city's storm-water management efforts," said Jon Capacasa, an official with the EPA's mid-Atlantic regional office.

But the same day also brought bad news: Climate change could soon make the Chesapeake's problems worse. A report from the Pew Center on Global Climate Change found that greenhouse gas pollution might bring more of the rain that washes pollution into the bay and more of the heat that can supercharge algae blooms.