The Chesapeake Bay could be set for a rebound

ENVIRONMENTAL progress in the Chesapeake Bay is as rare as a pearl in an oyster. So the quick recovery of the bay's blue crab population after almost 15 years of decline is cause for celebration for epicures and watermen alike. Even more heartening is a landmark settlement in a lawsuit by bay advocates, announced yesterday, in which the federal government committed to achieving specific pollution-reduction targets for the entire Chesapeake watershed over the next 15 years. If properly enforced, it could mean a sustained rehabilitation not just for crabs but for the entire ailing ecosystem of the bay.

First, the crab comeback. Credit for that goes to the two governors who signed a compact in 2008 to protect sooks, or female crabs, from being overfished. Timothy M. Kaine of Virginia (who's since completed his term in office) and Martin O'Malley of Maryland, both Democrats, took political heat from crabbers to safeguard one of the mid-Atlantic's signature natural resources.

Thanks to effective enforcement and crabs' quick maturation and natural fecundity, the governors' gamble appears to have paid off with lightning speed: After the governors sharply limited the harvest of sooks, the bay's crab population is estimated to have more than doubled in two years. Although it remains about a quarter below 1993 levels, the progress is dramatic.

At the risk of sounding a sour note, it's a pity the two states didn't act years earlier. Armed with an annual dredging census, scientists began warning in the mid-1990s that crabs were at risk; by the turn of the century, a bi-state commission was at work devising ways to stop overfishing. But the commission was disbanded in 2003 -- a victim of political opposition from watermen -- and the annual crab harvest, already depleted, wallowed below the historical average until Mr. Kaine and Mr. O'Malley acted.

Crabs, unlike oysters, are exceptionally well suited to a rapid rebound. But the point remains that it pays dividends when policymakers heed scientific evidence and apply it to managing a depleted resource. The question now is whether the gains in the crab harvest are sustainable, and whether state and federal authorities will act to improve the bay's overall health.

On that front, the news Tuesday that the Environmental Protection Agency agreed to a new regime of pollution-reduction targets could be a milestone. For the first time, the EPA has entered into a legally binding agreement to enforce pollution limits on the six states (plus the District) with territory in the bay's 64,000-square-mile watershed. Under the accord, strict caps on nitrogen, phosphorus and sediment flow will be monitored and reduced, with benchmark goals set every two years beginning in 2011.

The settlement is likely to face tough legal challenges from farmers, who would have to cut back sharply on the use of fertilizers and other runoff pollutants. The best way to lock in the agreement's goals is to enact legislation pending in the Senate, the Chesapeake Clean Water and Ecosystem Restoration Act. The bill, sponsored by Sen. Benjamin L. Cardin (D-Md.), would buttress the pollution-reduction goals against legal challenges, ensure they would be pursued by future administrations and provide the possibility of significant federal funding to make it all work. By putting the full weight of the federal government behind the bay's recovery, Mr. Cardin's bill would be a bulwark against further deterioration of a unique American waterway.