100,000 Gallons of Burnsville Sewage Leak into MN Valley Refuge

About 100,000 gallons of residential sewage leaked into Burnsville's Minnesota Valley National Wildlife Refuge in February.

The bottom rung of a ladder left in a manhole caused a blockage in Burnsville's sewer line and the waste to rise up eight feet into the refuge, Outdoor News is reporting.

The leak was discovered on Feb. 21 and by Feb. 23 bypassed the blockage and began removing the sewage, which had trickled down a creek into a wetland and Black Dog Lake.

“How long it was flowing before [Feb. 21], who knows?” Jeanne Holler, the deputy refuge manager at Minnesota Valley, told Outdoor News.

Workers are expected to complete cleanup this week, which will cost the city about $17,000 in contractor costs in addition to the time city workers spent cleaning up the spill.

Outdoor News has more about the consequences of the spill:

While much of the solid waste will have been removed, it’s likely liquids seeped into refuge waters, according to Holler. What might be the results? Among the possibilities, she said, are fish kills and increased algae blooms. The possible effects on waterfowl are unknown.

Outcomes are somewhat unpredictable, Holler said, considering “all the things people put in the toilet.”

Holler added that because water from Black Dog Lake is used for cooling at an Xcel Energy plant, it circulates more, something that could better mix and dilute the waste that makes it to the lake.