Sewer district seeks waiver from stricter discharge limits into Lake Winona
How to restore Lake Winona is a challenge that continues to vex, judging by a public hearing Wednesday evening about the sewer district's intention to seek waivers from new, stricter limits on what it can discharge into the lake.
The Minnesota Pollution Control Agency has reduced the amount of phosphorus and chloride the Alexandria Lakes Area Sanitary District can put into the narrow, shallow lake. The sewer system cleans waste water for just over 10,000 household and commercial customers and sends about 2.9 million gallons a day into Lake Winona, the first of a chain of lakes.
About 40 people attended the hearing, not counting the sewer district board, staff members and consultants. Many came from Lake Winona or the rest of the chain of lakes.
Warned that the cost of meeting state chloride and phosphorus limits could stagger toward $100 million, some in attendance said spending big figures might be worth it.
"The longer we wait, the more difficult it's going to be and the more our lakes are going to be endangered," said Corliss Stark, a former city council member who lives on Lake Winona. "We passed a $73 million school bond issue and nobody has gone broke over that."
The new chloride limit is 252 milligrams per liter of wastewater, about a third of what the sewer district now sends into Lake Winona. At levels higher than the new state limit, chloride can harm aquatic life. Chloride enters the treatment plant primarily through home water softeners and road salt.
The sewer district says the only way it could comply with the chloride limit is to send wastewater through half-mile deep shafts to avoid aquifers, by spraying wastewater over 5,000 acres or by discharging it into the Long Prairie River which is already considered an impaired water. The cost of meeting chloride limits range from about $70 million to $138 million.
Another option is to remove water softeners and create a centralized water softening system, which would have greater control over the amount of salt released, said Bruce Nelson, executive director of the sewer district.
Sewer district officials say they are fairly confident the state will grant a waiver on meeting the chloride levels, considering the cost involved and that chloride levels are a statewide problem.
They're asking for a conditional waiver on meeting phosphorus levels, arguing that a $14 million plant upgrade to reach stricter levels might not be necessary to restore Lake Winona to its natural state. Joe Bischoff, a scientist who studies shallow lakes, contends that carp need to be removed from the lake before the plant invests any money in further reducing its phosphorus emissions.
The invasive fish contributes to algae growth, he said. Once the majority of carp are removed and the rest managed, then underwater plants may begin to return, beginning a process of returning the lake to what Bischoff calls a "clear water" state.
One man asked what has to happen to begin the removal of carp.
Paul Nelson, sewer district board chairman, put it bluntly: "You figure it out," he told the man.
The sewer district doesn't own the lake and isn't responsible for restoring it, he said. All it controls is what it puts into the lake. The community, he pointed out, owns the lake and must figure out how to proceed.