Officials hope Lake Minnewashta zebra mussel treatment sticks

Zebra mussel shells covered a dock
Zebra mussel shells covered a dock on Lake Mille Lacs on May 6, 2015.
Dan Kraker | MPR News file

Officials with the Minnehaha Creek Watershed District say a copper treatment to kill zebra mussels on Lake Minnewashta in the southwest metro has been successful — so far.

Zebra mussels were discovered near the lake's boat access last month. Eric Fieldseth, the watershed's aquatic invasive species program manager, said the copper treatment was applied to the entire "Little Minnie" bay — an area of about 29 acres.

"These are still pilot treatments. We're still learning on these treatments the whole rapid response approach, how effective it is," he said.

Fieldseth said he hopes the treatment works better than a similar treatment on nearby Christmas Lake. In that case, officials treated a smaller area of the lake only to see zebra mussels show up again. They have since spread in the lake.

Still, Fieldseth says he doesn't expect the population to spike from year to year because Christmas Lake has less algae, a food source for the mussels, than other lakes.

Both Minnewashta and Christmas Lake are located south of Lake Minnetonka, which is infested with zebra mussels.

The Lake Minnewashta treatment cost about $30,000.

Your support matters.

You make MPR News possible. Individual donations are behind the clarity in coverage from our reporters across the state, stories that connect us, and conversations that provide perspectives. Help ensure MPR remains a resource that brings Minnesotans together.