TRAVERSE CITY, Mich. (AP) — Michigan officials pledged Thursday to work with farmers and municipal sewage treatment operators on preventing the kind of Lake Erie algae blooms that prompted a recent order not to drink tap water in Toledo, Ohio.
But they said more help was needed from federal agencies, particularly by establishing a national drinking water standard for microcystin, the toxin produced by blue-green algae.
They also called for a halt to the discharge of dredged sediments from Toledo's harbor into open waters, saying the material contains nutrients that feed noxious algae.
"The fact is, the algal blooms in western Lake Erie are the product of several key factors — municipal sewer discharges, farm and other surface runoff, invasive species like zebra and quagga mussels and weather," said Dan Wyant, director of the Michigan Department of Environmental Quality. "We can't control the weather, but we are determined to do all we can with the pieces we can address."
About 30,000 residents of southeastern Michigan and hundreds of thousands in Ohio were affected by the two-day order not to use water from the Toledo municipal system.
Wyant and Jamie Clover Adams, director of the Department of Agriculture and Rural Development, discussed the algae problem Wednesday in Chicago with officials from Ohio and the U.S. Environmental Protection Agency. They used the occasion to press for more federal involvement.
Of particular concern is the absence of a consistent threshold for determining unsafe levels of microcystin, which is released when blue-green algae dies. Wyant said. Michigan observes an international standard of 1 part per billion, but he contended a scientific analysis should determine if it's adequate as a U.S. standard.
Also needed is more study of the role that invasive mussels play in promoting algae growth and cycling of phosphorus in the water, as well as emerging technologies that could control them, he said.
On the state level, the DEQ will help sewage treatment plants in Michigan reduce phosphorus content in treated effluent, Wyant said.
Adams said her department would continue encouraging farmers to use best-management practices designed to keep fertilizers on fields nourishing plants instead of washing into creeks and eventually reaching the Great Lakes and other waterways. She argued that regulations to require compliance are not needed and seeking voluntary compliance was a more effective approach.
"I'm very confident that working with growers, we can accomplish the same thing that regulations would try to accomplish with a lot less fighting," she said.