WASHINGTON -- Pointing to signs that Chesapeake Bay is making at least a partial recovery from decades of pollution, state and federal officials said yesterday they plan to shift their efforts now toward restoring water quality and fish in the rivers that feed into the bay.
In a Capitol Hill briefing for Maryland's congressional delegation, state Environment Secretary Robert Perciasepe said that while the interstate cleanup effort to date has focused on restoring life to the main bay, its tributaries contain most of the spawning grounds and underwater grass beds so vital for fish. Two-thirds of the bay grasses that feed and shelter fish and crabs, for instance, are in the rivers.
"This has to be a very logical next step," Mr. Perciasepe said. Moving cleanup efforts into tributaries such as the Patapsco, Patuxent, Choptank and Potomac rivers comes after a sophisticated computer modeling study predicted the main bay's water quality will make significant improvements if Maryland, Pennsylvania and Virginia stick to their 1987 goal of cutting nutrient pollution 40 percent from sewage plants and farm and suburban runoff.
Nutrients are needed to maintain life, but the bay suffers from too many. Excess nutrients trigger massive algae blooms that block out sunlight needed by underwater grasses. And when the microscopic plants die and decay, they render vast stretches of bay bottom practically lifeless in summer by using up the oxygen in the water that fish need to breathe.
Multimillion-dollar efforts to upgrade sewage plants already have reduced one of the two nutrients to blame for the bay's decline -- phosphorus. Mr. Perciasepe said the other nutrient, nitrogen, which is even tougher to control because it also comes from runoff and air pollution, is at least leveling off.
"We're now trying to zero in on refinements to the strategy we had in 1987, not [making] wholesale changes," Mr. Perciasepe said. Governors of the three bay states and other officials are scheduled to meet later this summer to review the cleanup effort.
William Matuszeski, who runs the U.S. Environmental Protection Agency's Chesapeake Bay office, told the legislators that the cleanup effort is ready to shift its emphasis from upgrading water quality to restoring fish and plants.
"Living resources are the payout. That's what the public is interested in," he said. There are signs of improvement there as well, he said. More than half the 120,000 acres of underwater grasses that grew along the banks of the bay and its tributaries in 1970 have returned, he said, after shrinking to a low of about 15,000 acres in the late '70s and early '80s.
But William C. Baker, president of the Chesapeake Bay Foundation, contended that far greater efforts to control pollution, especially from farms, development and automobiles, would be needed before the estuary could be restored.
Mr. Baker said he feared the bay cleanup effort may be losing momentum even as it is beginning to show some results.