White Bear Lake seeks approval for lake cleanup pilot project

Varney Lake could be a lot cleaner and prettier come spring, if the city of White Bear Lake gets approval from the state to try an experimental cleanup procedure this winter.

The stormwater retention pond, located between White Bear Lake High School and the newly renovated White Bear Area YMCA, has become clogged with sediment that has dramatically reduced its capacity.

The Minnesota Pollution Control Agency (MPCA) made three grants last year to cities looking to clear out such sediments and harmful poly-aromatic hydrocarbons (PAH) from their stormwater ponds. Golden Valley and Circle Pines plan to use their grants to help pay for removal of the sediments and PAH to a landfill, the currently recommended procedure, said Don Berger MPCA state program administrator.

White Bear Lake plans a pilot project that would excavate the pond and build an 8-foot berm around the recovered materials. The MPCA and Minnesota Department of Health are reviewing the plan to ensure it is safe for residents and the environment, he said.

Mark Burch, the city's public works director and city engineer, said the entire cost of the project is estimated at about $250,000. The MPCA grant will cover up to $100,000 of that.

"The cost of disposing these materials makes these projects unbearable," he said. "We just can't fund them."

Additionally, if every city in the state tried to haul away all its PAH contaminants, "they'd inundate the landfills," Burch said.

Problem is widespread

The problem of sediment buildup in stormwater ponds faces cities throughout the metro area, Berger said. State legislators have directed the MPCA to catalog every stormwater pond in Minnesota, an effort that is ongoing, he said. Some cities have hundreds of stormwater retention ponds.

"These ponds were designed and engineered to protect the community from flooding damage," Berger said. "If you lose the capacity of these ponds, you run the risk of flooding damage."

Housing developments often were built around the ponds, but the amenity of having a nice small pond in view is lost as the sediment and PAH builds up.

If the pilot project at Varney Lake is successful, it has big possibilities for the rest of the city, as well as neighboring communities, Burch said.

Varney Lake has open space nearby, which is where the berm would be built. Other ponds are completely surrounded by housing developments, he said, but the sediment could still be used to build berms elsewhere in the city.

Burch said the city spoke with researchers at the University of Minnesota who have studied the characteristics of the contaminated sediments. "Based on some of that research, this material isn't going to migrate anywhere," he said. "The material is going to be encapsulated. We're saying, 'What's the risk?'"

The MPCA and Department of Health expect to complete their risk assessment by the end of January.

"I think it's safe to say across all state agencies, it's an emerging issue," said Berger of stormwater pond cleanup. "The folks that do water quality type work are all getting engaged in how to troubleshoot and manage the problem."

Emma L. Carew • 651-735-9749