For the bay, prevention may be the best remedy


Cleanup: Complex management and computerized solutions pale in comparison with simply reducing pollutants.

August 09, 2002|By Tom Horton | Tom Horton,SUN STAFF

SOMETIMES I THINK humans are genetically predisposed to favor technological solutions over limiting themselves, hardwired to spend tons of time and money on cures rather than little bits on caution and prevention.

Or maybe there's more money in selling solutions than avoiding problems in the first place - especially because human bookkeeping discounts nature's losses.

This week's sermon stems from a conversation with Rob Magnien, a scientist with Maryland's Department of Natural Resources who has taken a new look at where we are going with restoring Chesapeake Bay.

Magnien's calculations, which he stresses are more "big picture" than precision math, differ from the official measures of bay cleanup used by Maryland and the federal government.

The official measures come from a sophisticated computer model run by the U.S. Environmental Protection Agency. It estimates how much pollution typically comes from each kind of land use (forest, development, cornfields, pasture) across the bay's six-state, 64,000-square-mile watershed.

Then the bay model, as it's known, cranks in the estimated benefits of pollution controls, from farm management plans to sediment and storm water controls in housing developments.

The model shows that agriculture, one of the largest sources of the nitrogen and phosphorus whose excesses are damaging the bay, has made slow but significant progress in the past decade and a half - reducing nitrogen entering the bay by about 30 million pounds a year, and phosphorus by about 3 million.

Magnien, and Scott Phillips, a U.S. Geological Survey scientist, have done some estimating of their own, based on how much nitrogen and phosphorus enters the watershed from all sources of pollution.

They find it may actually have increased in the past decade and a half - from 1.44 billion pounds of nitrogen a year to 1.51 billion, and phosphorus from 316 million pounds a year to 330.

Not all of this gets to the bay. A lot is taken up by crops and natural vegetation or converted to harmless forms by natural processes in soils and rivers.

But it shows the potential for bay pollution, and that potential seems at least as high as it was in the 1980s, when serious efforts at bay restoration got under way. We have actually done a lot of cleanup, Magnien says, but we have also added about a million more people to the watershed.

Of all the big pollution sources - farming, sewage and industrial discharges, fallout from polluted air, urban storm water runoff, septic tanks, sewage treatment sludge spread on farms - only sewage plants and industries generate less pollution now than 15 years ago.

When Magnien looked at agriculture where the bay model estimates tens of millions of pounds of cleanup, he and Phillips found sales of commercial fertilizer across the watershed relatively unchanged from 15 years ago - likewise for the amounts of animal manure produced on farms. All this despite a significant decrease in farmland in the watershed.

This is perplexing because substituting manure for commercially purchased fertilizer was supposed to be at the heart of farm-pollution reductions. It doesn't seem as if it has happened.

"When you look at what we're still depositing on the land from sludge, animal waste, fertilizer, from the air, you gotta wonder how we're going to make a serious dent in" cleanup, Magnien says.

Which brings us to the question of limits, and a week I spent a couple of years ago on a farm tour of the Netherlands, where the Dutch are struggling with fertilizer and manure pollution in excess of ours.

They regulate farmers to an extent that ours, who recoil at the thought of any regulation, can scarcely comprehend.

The Dutch government requires 95,000 farms to fill out 3 million forms and track their production and use of manure virtually to the ounce. If farmers have an excess (i.e., a potential for water pollution), they are taxed on it.

Manure there can only be spread at certain times of year, and all of it must be immediately injected or plowed into the soil to prevent its nitrogen escaping. One experimental farm uses precisely timed grazing periods for cows, so their wastes are mostly captured in the barn, rather than falling on open pasture.

The Dutch were making great progress in controlling farm pollution - but not nearly enough, according to a pollution regulator from the European Union who traveled with us.

The country just had too many animals, he explained; and even with the most sophisticated management, he thought the Dutch would never meet water quality goals without reducing the size of herds and flocks.

And that is what Magnien is saying (and what the troubled bay is saying, too): unless we make large, real reductions in the pollutants we generate, no amount of management or computer modeling will heal the waters.

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