Cedar Lake, near New Prague, gets C’s, D’s and even F’s for water quality. Scott County’s top environmental manager has studied 200 lakes and believes he has never seen one as badly infested with one particularly damaging invasive weed.
Oh, and one more thing. It’s the lake in Cedar Lake Farm Regional Park, one of the major new installations in the south metro of the past decade.
The good news: Its status today as the centerpiece of a park has pushed a body of water that’s graded D overall higher on the list of priorities for environmental cleanup.
The bad news: Don’t expect results for many years to come.
“It’ll be 10 to 20 years for many lakes, and Cedar Lake is probably the most difficult of all, because it’s so shallow,” said Paul Nelson, natural resources program manager for Scott County. “It’s probably better classed as a reservoir than a lake.
“Historically, it’s been more like a wetland,” until the state injected more liquid.
What to do
County commissioners peppered Nelson with questions this spring after eyeing a status report classing a lake at the heart of one of their proudest initiatives as badly impaired. What can be done, what is being done, when can results be achieved?
Scientists say that there’s lots more money being deployed than before, but that you’re dealing with severe issues remaining from decades of buildup, with really drastic, faster solutions being ruled out for reasons of public alarm at the side effects.
“Isn’t the ultimate solution to drain it and start over?” asked Commissioner Joe Wagner.
“That’s a very good question,” Nelson said. “We’ve looked at that. But there’s much concern among [the slightly more than 300] shoreline owners. They are concerned about how quickly it would fill up afterward. It could take several years. So we dismissed that because of public concern.”
But the status quo is tough as well, said Melissa Bokman, senior water resources planner.
“It can affect the ability to swim in it. Last year, we had pretty bad blue-green algae bloom, which is a bacteria that looks like algae. When it decomposes it smells like cow manure. We were getting calls saying some farm was affecting the lake. We went out and it was the decomposing algae.”
One new attempt at a solution: to lure sportspeople into a bowfishing contest annually, hoping that thousands of dollars in prizes for the greatest number of carp yanked out of the lake will help.
“The common carp is a nonnative invasive aquatic species that severely impacts water quality in shallow lakes and wetlands,” a flier reads. “Their feeding habits disrupt shallow-rooted plants, muddying the water and releasing phosphorus from lake sediment...”
The first contest, in 2013, was a bit of a dud: Severe weather blew through, and only the bravest souls kept at it.
Another try in May had to be postponed for weather reasons, and then last weekend’s makeup date was hit again by rain, said Brad Eller, a lakes district board member.