The recent signing of a four-part pact on Chesapeake Bay protection was an important step forward. The fact that differences remain between the approaches of Pennsylvania's and Virginia's governors on one one side and Maryland Gov. William Donald Schaefer and the Environmental Protection Agency's William Reilly on the other is less significant than the fact of an agreement.
To be sure, neither Robert Casey nor Douglas Wilder has to deal with the outrage of Eastern Shore farmers and developers fighting any and all attempts to restrict land development moves. Mr. Schaefer, still chafing over erosion of peninsula support in his last election, cannot ignore the protests. The EPA's Mr. Reilly, for his part, represents a federal administration already determined to rewrite the definition of wetlands and strip some protection from critical acreage around the bay.
The new agreement promises to reorient strategies for the Chesapeake watershed. Rather than try to block off pollution after it has been introduced into the environment, the new approach will be to limit or prevent its introduction at all. In Pennsylvania, for instance, where farm runoff into the Susquehanna is a continuing problem, that means a harder push for no-till farming and other reduced-fertilizer and reduced-pesticide strategies.
The EPA report on the adverse effects of higher temperatures on the health of the bay, publicized just as the new agreement was signed, argues for closer attention to what happens on the shoreline. Global warming, one potential villain, may be at work, but the local impact of a population jump from 1970's 3.9 million to 4.7 million in Maryland alone cannot be ignored. The number of miles Marylanders drive has doubled over the last 20 years. Not only does auto exhaust warm the air and pump acid-rain-producing nitrogen oxides into it, but the thousands of miles more of paving for those vehicles push ever more warm rainwater into the bay as runoff.
The Chesapeake, America's largest estuary, is Maryland's greatest natural resource. It is threatened by overdevelopment in the state. In the next 30 years, nearly 700,000 acres are expected to be developed -- two-thirds of the 1.1 millions acres that were developed in all of Maryland's 360-year history. The story is the same in other watershed states. That puts severe pressure on the bay which must be relieved. The five-party agreement comes at a critical time. We only have one Chesapeake Bay; preserving it has to be the first priority.