Pfiesteria's surprising benefit Restoration: Despite the microorganism's undesirable byproducts, the toxin finally is focusing attention on the bay.

On the Bay

December 05, 1997|By Tom Horton | Tom Horton,SUN STAFF

PFIESTERIA piscicida, the toxic microorganism that erupted in Chesapeake waters this summer, was nothing you'd wish for; yet, it could move forward the bay restoration agenda as nothing has in years.

Fish with ugly lesions, watermen with acute memory loss, a staggered seafood industry -- these byproducts of Pfiesteria outbreaks were what it took to bring long-needed attention to the bay's biggest, but least sexy, form of water pollution.

That would be nutrients -- phosphorus and nitrogen -- in sewage and fertilizer runoff from the land. They turn clear water murky with algae, cut off light and suck up oxygen, killing aquatic grasses and critters.

And now, they may be linked to Pfiesteria and a range of other toxic algae blooms.

Outside of scientists and environmental professionals, it has proved difficult to raise alarm about nutrients, about overfertilization, about too much of a good thing (nitrogen and phosphorus being essential to much life).

With all respect to Rachel Carson, I have wondered how "Silent Spring," her masterwork on toxic chemicals, would have fared if she substituted "too much of a good thing" and disappearing underwater grasses for vanishing eagles and songbirds dropping dead from chemical poisons.

And yet, in the Chesapeake and around the world, this overdose of nutrition, washing from farmland, industrial animal operations and human sewage, is suffocating coastal waters -- as epidemic and grave a threat as DDT ever was in Carson's day.

Which brings us back to Pfiesteria, and the investigation conducted by Gov. Parris N. Glendening's blue-ribbon commission. Its findings provide ample basis for actions by the next legislature.

The report of the commission, chaired by former Gov. Harry R. Hughes, could be more forceful and focused, but overall strikes a good balance on a complex issue.

It makes clear that there can be no return to the status quo in managing nutrient runoff from the land if we are serious about better water quality.

It proves beyond a doubt -- though you have to wade through a lot of flat prose and scattered statistics to get it -- that state officials have exaggerated the effectiveness of voluntary nutrient controls on farms and poultry- growing operations.

Yet, in a tone of accommodation, the report notes agriculture is not in this alone; rather, it is part of a cheap and bountiful food system that includes us all -- as must any solution.

The report concedes the links between Pfiesteria and nutrients need more study. Some outbreaks occur without high nutrient concentrations. Neither is it known whether limiting nitrogen or phosphorus, or both, would be the best preventive.

But a key section, based on the consensus of leading bay scientists, concludes: "Decreasing nutrient loads will likely reduce the risk of outbreaks."

And just as important, the report puts this in a broader context of something we should do anyhow: "Reducing nutrient levels is good for aquatic life, human health and water quality and should be a focus of our pollution control efforts."

That the bay's nutrient problems from agricultural runoff are bigger than advertised, the report leaves no doubt.

On the lower Eastern Shore, where Pfiesteria blooms occurred, there is poultry manure enough to meet virtually all farmers' needs for fertilizer.

But large amounts of commercial fertilizer are still being purchased and applied on top of this, despite the adoption of highly touted nutrient- management plans, under which farmers

supposedly apply only as much fertilizer as a crop needs.

Worse, more than half of farmers in a survey on the lower Shore said factors other than nutrient-management plans governed their manure spreading. "Disposal needs," said 21.7 percent, while another 35 percent replied, "field was open" (without crops).

Ominously, phosphorus has built to such high levels in soils on the lower Shore, where chicken manure has been spread for years, that it will remain a pollution problem for some time even if no more manure is spread.

A key recommendation for cleaning up farm runoff is to make progress "demonstrable." The current voluntary system has no accountability.

Though agriculture in the region hit by Pfiesteria is the largest source of nutrients, the commission also targeted septic tanks and lawn fertilization.

Septic tanks are one of the most uncontrolled sources of nitrogen to the bay -- an estimated 3.7 million pounds per year. The recommendation that new septic installations employ state-of-the-art nutrient controls is long overdue.

The recommendations to make nutrient management truly effective on all farms would go a long way to help the bay, without putting a crushing burden on farmers or the poultry industry.

The report outlines many practical solutions to reduce nutrients, ranging from changes in poultry feed, to composting manure and planting pollution- filtering strips of trees along waterways.

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