Maryland's sewage treatment plants will need additional money for upgrades to reduce nitrogen pollution to levels that state and federal regulators are demanding, plant operators said yesterday.
But they argued that setting mandatory limits on nitrogen discharges in sewer plant permits is unnecessary because voluntary upgrades are already cutting as much pollution as possible.
"We feel that we've demonstrated in Maryland that we can meet the goals through voluntary means," said Michael Bonk, director of Anne Arundel County's utility operations and president of the Maryland Association of Municipal Waste Water Agencies.
The Chesapeake Bay Foundation called this week for mandatory nitrogen limits on permits issued to the state's 66 sewage treatment plants. The permits, issued by state and federal environmental agencies, come up for renewal every five years.
Nitrogen is the bay's chief pollutant and sewage plants contribute about 20 percent of it. Agriculture contributes another 41 percent through runoff from fertilized fields.
Nitrogen contributes to the growth of algae that block sunlight and kill underwater grasses that are needed to produce oxygen and naturally clean the bay.
Administrators from the District of Columbia and six states that encompass the bay watershed agreed in March to cut nitrogen from sewer plants by 39 million pounds a year by 2010.
"Without significant grant funding, it's going to be very difficult to meet those goals by 2010," Bonk said. He declined to say how much sewage plant upgrades would cost, but a task force in November estimated the price tag at $2.7 billion to $4.4 billion baywide.
Bonk and other plant operators said they're making improvements through cooperative efforts with state and federal regulators.
In Baltimore, city officials noted a $200 million upgrade that will reduce nitrogen from the Patapsco sewage treatment plant to levels that the Chesapeake Bay Foundation recommended this week. The plant is one of the state's largest.
"Everybody will benefit from what we're doing," said Robert T. Mohr, chief of wastewater facilities for the city Department of Public Works.
State regulators say sewage treatment plant operators are eager to improve their equipment, making additional regulations unnecessary.
Since 1985, the state's major sewage treatment plants have cut nitrogen discharges in half, to 10 million pounds annually, according to a Maryland Department of the Environment spokesman.
But the bay foundation says that there's room for improvement with new sewage treatment technologies available.
"We're saying, `That's not enough,' and that now, we're able to get nitrogen levels down even further with very little expense," said Theresa Pierno, a bay foundation vice president.