State targets household pollutants Each Marylander produces 5 1/4 pounds of pollutants yearly

'The fingerprint of God'

Measures would help only on small scale, scientist says

January 25, 1998|By Heather Dewar | Heather Dewar,SUN STAFF

Each Marylander contributes an average of more than 5 1/4 pounds of harmful nutrients to the Chesapeake Bay each year in the course of his or her daily routine, according to the Environmental Protection Agency.

Gov. Parris Glendening wants to rein in some of these everyday pollution sources to help prevent outbreaks of Pfiesteria and other toxic microorganisms. While the centerpiece of the governor's plan, unveiled Wednesday, would regulate farm runoff into the bay, his proposal also attempts to control the nutrients that the average Marylander adds to the bay's overload.

Is it worth it? Would the measures that the governor has proposed -- such as requirements that lawn-care companies test soils before fertilizing large properties, and new standards for septic tank designs -- produce enough improvement in bay-water quality to justify the effort and unknown expense?

Taking the bay as a whole, probably not, said ecologist Tom Fisher of the University of Maryland's Center for Environmental Studies. But if the goal is to protect a single creek or stream, the measures will help.

"In the big scale, it's not going to solve the problem," said Fisher. "There's no getting around the fact that agriculture is the single biggest contributor to nutrient levels in the Chesapeake. But if you're worried about your cove, putting less lawn fertilizer on might make a big difference."

Science teacher William Moulden is concerned about the Severn River, and he is sure that small steps to curb nutrients are important. He has prodded residents of waterfront Sherwood Forest in Anne Arundel County to build an experimental marsh to catch runoff from septic tanks.

Tests show that nitrogen and phosphorus levels in the water flowing from Sherwood Forest into the river have gone "from very high to almost zero," Moulden said. It's a drop in the bucket, but it helps make the Severn cleaner, he said.

In 1996, the states around the Chesapeake Bay deposited 280 million pounds of nitrogen and 17 million pounds of phos-

phorus into bay waters, according to an October 1997 EPA report. These nutrients fertilize algae blooms that cloud bay waters, lower oxygen levels, cut off light and encourage microorganisms such as Pfiesteria to multiply.

Bay restoration goals call for reducing yearly additions of nitrogen by 186 million pounds and phosphorus by 10 million pounds by the year 2000. Those goals won't be met on time, officials announced last spring.

About one-quarter of the nutrients reaching the bay are airborne -- including nitrogen-rich gases from the tailpipes of the cars and trucks we drive. The amount of locally produced air pollution reaching the bay is hard to measure, but it's increasing as residents' commuting distances increase, according to Lewis Linker, a computer scientist at EPA's Chesapeake Bay Program.

Of the waterborne nutrients reaching the bay, about 45 percent comes from agriculture, the EPA estimates. The rest come from sources related to development, such as septic tanks and fertilized lawns and golf courses.

3 pounds a year

Each Marylander contributes almost 3 pounds per year of nutrients through household sewage and the use of industrial products. Seepage from septic tanks and runoff from lawns produce about another 1 1/2 pounds per person; runoff from paved areas adds about three-quarters of a pound.

That estimate by computer scientists at the Chesapeake Bay Program doesn't count the nitrogen that comes out of vehicle tailpipes, some of which ends up in the bay. And it doesn't include the nitrogen and phosphorus used to grow food.

Improvements at sewage treatment plants could reduce the amount of nitrogen reaching the bay by 5.5 million pounds, according to EPA estimates. Better septic tank designs could reduce nitrogen by 12 million pounds. More careful use of fertilizer by homeowners and landscaping companies would mean a reduction of 45,000 pounds.

Sewage treatment

While proposing the state's first farm-by-farm controls on fertilizer use, Glendening wants the legislature to spend $6.9 million to upgrade sewage-treatment plants, starting with the Lower Shore. He wants to help counties devise more efficient designs for new septic tanks, and he wants commercial landscapers who care for golf courses and other large tracts to be required to apply only as much fertilizer as needed.

Scientists say these measures will be good for the bay's water quality and will probably reduce toxic outbreaks, but they won't have much short-term effect.

"Incremental changes will have incremental results," Fisher said. "We really don't know enough about it to say, 'This is really going to fix the problem.' Politically it may be necessary for the governor to say that, but scientifically we don't know enough to say that."

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