ANNAPOLIS -- On a radio talk show the other day Will Baker, head of the Chesapeake Bay Foundation, and David Carroll, Maryland Gov. William Donald Schaefer's man on the Bay, were slapping each other on the back over the latest save-the-Chesapeake success.

A group of high-level politicians had signed another "historic agreement" to clean up the nation's largest and once most productive estuary, which is enduring slow death by strangulation.

Virginia, Maryland, the District, Pennsylvania and the U.S. government had pledged anew to stem the Bay's decline.

But hang on. Didn't all this happen already, four years ago, when the previous historic agreement to clean up the Bay was signed at a George Mason University "summit"?

Wasn't everyone just as optimistic and enthusiastic back then? Hadn't the Environmental Protection Agency just spent five years and $27 million to determine the Bay's principal distress: that it was choking to death on excess nitrogen and phosphorus?

Maryland Gov. Harry Hughes and Virginia Gov. Charles Robb congratulated each other then. Now it's Schaefer and Gerald Baliles, but the message hasn't changed.

So what exactly has changed in four years?

On the water, not much for the good.

Rockfish are gone, of course, at least so far as the Maryland fisherman is concerned. Commercial and sport seasons were closed for fear that the state fish would disappear from its home waters. While rockfish stocks have rebounded somewhat under the protection, there is no hint of a reopening.

Ducks are fast disappearing. To slow the decline, hunting season was shortened to 40 days two years ago and daily limits were cut back. In places on the Bay where ducks used to darken the sky, you hardly see one anymore. That's largely because . . .

The grass is gone. Rooted aquatic vegetation, great flats of which once harbored waterfowl, crabs, fish and the minutiae they feed on, remains absent from most shallows.

Why? The EPA said excess nitrogen and phosphorus from treated sewage and farm runoff were acting as aquatic fertilizers in the Bay, creating coffee-colored algae blooms to cloud the water. Algae blocks sunlight, which the plants can't live without.

When the algae dies, it does double damage, EPA reported, gobbling oxygen to decompose and leaving the surrounding water lifeless. Watermen think that's partly why . . .

Oysters are gone. MSX, a mysterious virus, killed up to 95 percent of them in much of the Bay last summer, but oystermen and scientists say the shellfish in many places already were in steep decline, stressed to exhaustion by oxygen depletion.

Now comes word that Maryland is readying a management plan for its dwindling yellow perch. These bright harbingers of spring start traveling up Bay tributaries to spawn in February, providing the earliest sport of the season for anglers.

Lately, yellow perch spawning has been a flop, apparently because of acid rain, another of the Bay's multitudinous enemies.

The yellow perch management plan will be announced today. Rumors cite everything from a statewide ban on fishing during spawning to a limited closure of streams already abandoned by the little fish, which appears more likely. In any case, no one expects good news.

What I wonder, given that so many Bay natives remain in distress, is where anyone finds fuel for optimism and back-slapping over the latest save-the-Bay plan. Do these folks get out on the water?

I do, and where I live the creek just gets worse. No fish of consequence are left. Even crabs stored in floats at the neighbors' docks turned belly-up last summer, and crabs can tolerate just about anything.

Fifteen years ago, the locals say, this creek was full of life. In the winter there were pickerel and yellow perch. In summer came crabs, white perch and the odd rockfish. Bay grass was thick around the shoreline and the water was clear.

But around the bend from us lies the Annapolis sewage treatment plant, 10 million gallons a day capacity. Despite the last Bay cleanup agreement, it still spews nitrogen and phosphorus as Anne Arundel County grows.

Before the big freeze last week, tiny sprouts of submerged grass poked up in the shallows along the beach here, offseason remnants of better times. (Since algae doesn't bloom in winter, some grass briefly survives in the pale sunlight.)

But come spring the river will warm and, fertilized by a cloud of treatment plant effluent, go brown again. The grass will die and by July we'll have our watery desert back.

Is the Bay getting better?

Not here it isn't. And to hear those who work or live elsewhere in Bay country tell it, it's no isolated phenomenon.

No doubt leaders of Maryland, Virginia, the District, Pennsylvania and the EPA are sincere in their ambitions. Already, long-range projects are under way to reduce nutrient loads, though they appear woefully underfinanced.

But when politicians start applauding the latest Bay accord, it's a worry no one points out to them the insufficiencies of the last one. While they're cheering, the Bay is still dying.

The reality is that cleaning the Chesapeake is a long and dirty job that will cost huge amounts of money and energy. Cause for celebration, sadly, is decades away.

The federal government spent nearly $1 billion and 10 years to fix up one sewage plant on the Potomac -- Blue Plains. Long-term solutions for the Bay will be far more expensive and time-consuming than that.

Is government willing to make the sacrifice?

Every four years the politicians get together to say so.

But so far, the evidence says no.