The giant, lake-eating milfoil invasion is back.
No, that’s not a scary 1950s movie; it’s a sad situation for those who live or recreate on Silver Lake located in Columbia Heights and St. Anthony Village.
The lake underwent a treatment last year to tame the Eurasion milfoil, and the results were good — at first. It was estimated that the infestation in the lake was reduced from 69% to 21%. It didn’t last.
By August of last year, the milfoil made a comeback.
Doug Jones, a member of the lake’s homeowner’s association, said, “It came back with a vengeance. It has overwhelmed the entire lake. It clogs your motor. You can’t fish. If you cast a line, all you get is weeds.”
Jones said the number of boats on the lake has been drastically reduced. “Even the kayakers are having problems.”
Last year, the Department of Natural Resources allowed the lake owners to attack 15% of the lake, an effort to protect the lake’s native habitation by allowing it to survive the herbicide.
This year in April, with the milfoil expanding rapidly, the use of fluridone, an organic compound, was increased, and again, so far, the results have been good. A problem, though, is that the heavy rains this spring have diluted the fluridone and the homeowners want to boost the amount of it in the lake.
The lake is administered by a host of different agencies including the two cities, Hennepin and Ramsey Counties, the Three Rivers Park System and the Rice Creek Watershed District.
Brian Vlach, a senior manager of water resources for the Three Rivers Park District, said a management plan is being implemented for Silver Lake that includes the DNR, the homeowners, Three Rivers, Rice Creek and the cities.
“Last year we did the 15% treatment, and this year we got a variance from the DNR to do almost the whole lake,” Vlach said. He said Three Rivers will monitor the milfoil in the lake.
Vlach said that this might be a three-year or longer project. “We’d like to do the whole lake treatment for consecutive years to get the milfoil under control, and then just do spot treatments after that.”
He said that once the milfoil is under control, it’s hoped that the native vegetation, without the competition from the aggressive species, will come back. However, he also said there is also curly leaf pondweed (CLP), another invasive weed, in the lake, and it may try to replace the milfoil. CLP has also been known to choke lakes and produce an algae bloom.
Eventually, he said, the goal will be to restore the fish population in the lake.
Both St. Anthony and Columbia Heights have donated $2,000 each to the project, and each member of the lake owners’ association has donated $200 for the treatments this year.
Jones said the work is being spread out through the association. “This has become all encompassing, and so many people are taking part of the workload such as Tim Johnson, April Chu and Lilly Fee.”
A problem for the lake, as with most metro area lakes, Jones said, is that storm sewers drain into the lake. This can bring harmful chemicals into the lake, along with trash and other pollution. Jones said a campaign was done recently to inform people living in the area around the lake about the storm sewer connection.
Jones said the money for the treatments has been exhausted at this point, and the association will meet to discuss further funding. Jones said the cooperation was at near 100%.
Silver Lake is 70 acres in area and has a maximum depth of 47 feet. It is the home of Silverwood Park, one of the busiest regional parks in the area.
Doug Jones, who has led the homeowners’ association battle against the Eurasian milfoil infestation at Silver Lake, said the constant rain has diluted the chemical used to kill the plant. (Al Zdon)
A screenshot from a video shows an area dense with Eurasian milfoil in Silver Lake. The plant crowds out native species and reduces biodiversity. (Doug Jones)