Silver Lake has had a tough time in the last year or so, but a group of local homeowners and a handful of state, county and city agencies have teamed up to start a revival of the Columbia Heights and St. Anthony natural resource.
Two major, and related, problems for the lake are an infestation of Eurasian watermilfoil and a major fish kill due to a lack of oxygen in the lake.
Milfoil has been choking the lake bottom for the past three years, and when an aerator broke down this past year, thousands of fish died over the snowy winter from lack of oxygen.
The lake has had an aerator since 2021 near the beach area.
The lake covers 70 acres and has a maximum depth of 47 feet.
The local effort was led by Doug Jones who owns a home on the lake’s western shore. Jones and others were dismayed at the condition of the lake, particularly the milfoil infestation. “You could only go a little ways in your boat and you’d have to stop and back up to get the weeds out of the propeller.”
Jones started with the lake’s homeowners’ association, but soon made contact with the Department of Natural Resources (DNR), the Three Rivers Parks District, the city of Columbia Heights, Rice Creek Watershed District, Hennepin and Ramsey counties and private firms.
One of those connections was with Lake Restoration, a company out of Rogers, Minn. The company was hired to treat 15% of the lake, the most allowed by DNR regulations. The treatment was done on June 21. It was limited to 15%, which is about nine acres of the lake, because large uses of the herbicide could negatively affect natural vegetation in the lake.
The treatment was mainly done near the beach, the fishing pier at Silverwood Park and other areas where the infestation was strong.
April Londo, invasive species specialist with the DNR, said the chemical used in the lake was Diquat, which has been approved by the Environmental Protection Agency for use near humans and native plants. She said the Three Rivers Park District is monitoring the lake’s vegetation.
“A study done by Three Rivers showed that the treatment had reduced the invasive milfoil from 69% of the lake to 21%,” Paul Kretsch, a spokesman for the company, said.
Jones concurred. “It really knocked it down,” he said.
Kretsch noted there was 100% cooperation from the homeowner’s group. “It makes a plan much easier when everyone’s on board.”
The $5,000 cost of the treatment was borne by the homeowners, but the city of Columbia Heights also chipped in, and the Three Rivers Parks District provided the mapping for the lake.
New signage at the lake’s public accesses will warn people about bringing invasive species into the lake, and the necessity of having a clean boat.
A key player in the effort to fix the lake is the Three Rivers Park District, a regional authority with over 27,000 acres of parks and trails in the area.
“Silver Lake is a typical lake for the Metro area,” said Brian Vlach, senior manager of water resources. “It has the same issues as other lakes in our park district.”
He said the lake was somewhat unique because of how fast the Eurasian milfoil spread. “When we tested two years ago in 2021, the milfoil only covered 7% of the lake, but now it’s up to 60 to 70%. It’s really affecting the recreational use of the lake.”
Vlach said the fish kill on Silver Lake was not just due to the failed aerator, but because of the hard winter.
“It stresses the fish because they have no refuge to go to find oxygen. They are dying under the ice. Even when we got to the open water season, they were still dying.”
Three Rivers is working with the homeowners to develop a long range plan for the lake. With such a plan, the efforts to control the milfoil may be able to be beefed up beyond the 15% limit.
Three Rivers has a special interest in Silver Lake because it operates Silverwood Park. “Every one of our parks is unique, but Silverwood is noted because of the arts features, the sculptures in the park.
“And it’s a park that pulls from the diverse communities around the lake.”
The District is also working on creating fishing platforms on one of the lake’s islands.
The DNR has been stocking the lake for many years, and stocked it again this past spring after the fish kill. The lake mainly has panfish, but also some larger fish, including catfish.
This year the lake was stocked with adult sunfish and walleye fry, said the DNR’s Londo.
“We also purchased a new aeration system, and will be working with the city of Columbia Heights this summer and fall on getting it installed in time for the winter of 2023-24.”
Londo also said the lake association can do a formal plan for the lake that would allow the use of other herbicides, under the direction of the DNR.
The Rice Creek Watershed District has also had a hand in trying to keep Silver Lake a viable natural resource. They have been doing pollution studies on the lake dating back over a decade.
“We know that invasive milfoil has exploded on the lake, but the treatment this past month seems to have been very successful,” said Matt Kocian, lake and stream project manager for Rice Creek.
He said another effort that has borne some success has been working with New Brighton, Columbia Heights and St. Anthony on stormwater management.
He said the fish kill at the lake was strong this spring, as it was at other lakes, but he said sometimes those kills can actually help the lake in the long run, as the surviving fish get stronger and bigger.
Invasive milfoil tends to take over lakes, outcompeting the native vegetation, affecting phosphorus levels, and creating conditions that can kill fish.
“We lost thousands of fish,” Jones said, “It was just a huge, huge fish kill. We lost bass, walleyes, sunfish, perch. It was great for the turtles, though. They love to eat dead fish.”
The goal, Jones said, is a lake that can be used recreationally by local people. “There should be fishing for little kids. But the weeds are so bad. You catch weeds every time you cast from shore.”
Doug Jones, who helped organize the homeowners at Silver Lake to reduce the Eurasian watermilfoil infestation, points out the milfoil on his shoreline on the west side of the lake. The lake will also receive a new aeration system from the Department of Natural Resources that will benefit the fish in the lake. (Photo by Al Zdon)
