The watershed district covers 65 square-miles stretching from Shoreview to Woodbury; it includes Little Canada, along with parts of Roseville, Maplewood, North St. Paul, St. Paul, and other cities. The district removes carp from its lakes because the non-native species can be detrimental to water quality.
“[Carp] are bottom feeders, and they do a real good job in stirring up the lake bottom sediments,” Bartodziej said, adding the sediments contain phosphorous, which feeds algae blooms. Swimmers and boaters know the blooms for the smelly, green conditions they create on and in the lake.
Maintaining and improving water quality within its area is the Ramsey-Washington Metro Watershed District’s main mission, Bartodziej said.
Beyond its work involving the Phalen chain of lakes, he said in recent years the watershed district has done extensive work at Keller Golf Course in Maplewood, converting no-play areas around the fairways into high-quality natural areas.
“That golf course has the highest number of natural areas, more than any other golf course in the metro area,” Bartodziej said.
The carp caught at Gervais Lake and elsewhere are involved in the watershed district’s work in creating natural areas. Bartodziej said most of the fish are given away and used as fertilizer at a greenhouse facility, which is operated by Ramsey County Corrections.
The facility grows Minnesota native plants and the watershed district uses them in its restoration projects.
As for how the six-pound koi ended up in Gervais Lake, people on the Ramsey-Washington Metro Watershed District’s Facebook page speculated a heron scooped it out of a backyard koi pond and dropped it into the waters.
While Bartodziej agrees the fish likely came from a koi pond, he said the explanation is likely more mundane: A human put it in the lake.
“[They] got tired of the fish or it got too big,” he said.
Mike Munzenrider can be reached at mmunzenrider@lillienews.com or 651-748-7813. Follow him on Twitter @mmunzenrider.