Runoff pollution figures aren't exactly accurate

THE BALTIMORE SUN

YOU'RE a chronic overeater. The doctor says cut back the calories or exercise hard, preferably both. What do you do?

If you're the Maryland Department of Agriculture (MDA), you shop for clothes, hoping to give an illusion of slenderness.

We're not talking about fat bureaucrats -- rather about a polluted Chesapeake, over-enriched with nutrients from farm runoff -- and an agency ducking its responsibility for reducing them.

Ironically, this became clear at Gov. Robert L. Ehrlich Jr.'s Aug. 5 summit on agricultural nutrient pollution. Staged by the agriculture department, it was a valuable day that solicited useful input from farmers throughout Maryland who came to help the bay.

But the subtext was a continuation of the department's all-too-familiar attempt to paper over the seriousness of the farm runoff problem.

"Maryland farmers have met or exceeded most of the milestones needed to achieve Chesapeake Bay goals ... strides ahead of other bay [pollution sources]," proclaimed the information packages handed to the public and press.

The package had the department's official progress numbers for every bay tributary in the state, all documenting impressive reductions in the nitrogen and phosphorus in runoff.

But the numbers are bogus, wildly over-optimistic -- and MDA, as does every agency involved in the bay cleanup, knows it.

If you believed the department's progress reports, you'd wonder why farmers were wasting their time at the governor's summit, wonder why the Chesapeake Bay Foundation is calling for billions of dollars to help agriculture clean up.

A careful reader might have noted the department claims as its source, in a tiny-print footnote, the Environmental Protection Agency Chesapeake Bay Program's computer model of the bay's watershed.

Therein lies the rub. The model is perhaps the best in the world at computing how changes in pollution from air, sewage, development and farming play out, regarding bay water quality, across a six-state, 64,000-square-mile watershed.

It's an exceptional tool, and EPA will significantly improve it by 2006. But it's universally acknowledged to be weak in calculating agricultural pollution.

For starters, EPA's modelers take at face value the information they get from agencies like MDA on how many farmers are using so-called "best management practices," or BMPs to reduce pollution.

Maryland reports levels of BMPs far in excess of other states in the watershed -- levels that experts throughout the bay region feel are unrealistic, and have so told the department.

The model also assumes these best practices are all being implemented 100 percent, that they work in the field as well as in the laboratory -- they never do -- and that they are all maintained forever.

On top of that, the current model can't count some important sources of agricultural pollution, like airborne nitrogen from manure and phosphorus buildups from overusing it in manure.

Bottom line? The model, even assuming accurately reported BMPs, might be 20 percent to 40 percent over-optimistic, scientists familiar with it say.

That's usually not a problem, because everyone recognizes the model's not reality, and exercises caution. Except MDA.

It's not just the computer model that gives the lie to their progress reports. It's the good science that the Ehrlich administration has said it will base its environmental decisions on.

That science has recently shown, in a several-year experiment in Maryland's Pocomoke River drainage, that if you do almost everything we know how to do to reduce polluted farm runoff, you get a 24 percent decline in nitrogen.

MDA in that same region claims a 39 percent decline in nitrogen -- and no farm there is using anywhere near the pollution-reduction techniques of the Pocomoke experiment.

On the Choptank River, MDA claims a 42 percent reduction in nitrogen, but in the river, whose pollution comes 85 percent from farmland, nitrogen has been rising or shown no decline in more than 30 years of measuring it.

Other studies in Maryland, Virginia and Pennsylvania have shown little or no decline in production of farm manure, or in farm purchases of fertilizer.

"Overall, we're not seeing the drops in pollution you'd expect from our reported implementation of agricultural BMPs," says Rich Batiuk, a scientist at the Chesapeake Bay Program.

Farmers and the public need the truth, now. Maryland is about to allocate how much agriculture and other sources, such as sewage plants, must reduce pollution to restore the bay by 2010.

Agriculture faces a huge potential cleanup, about 10 million pounds of nitrogen. MDA would have us think they have already done that much -- the amount claimed based on the computer model -- and done it voluntarily.

But it's a lie. Agriculture hasn't come close to that sort of progress -- not anywhere in the world; and doing it won't come easy or cheap.

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