Sad News – Zebra Mussels in Our Lake – What Do We Need to Know and What should We Be Doing Now?

Everybody by now probably knows that zebra mussels have been found in Lake Minnetonka. I and everybody else who loves Lake Minnetonka hoped this day would never come. It is truly sad news for everyone. But, now that they are here, what next?

As of now, it appears the infestation is limited to Grays and Wayzata Bay and the Lower Lake south to Big Island. All appearances are that we are very early in the infestation. Crews from the Minnesota Department of Natural Resources and the Minnehaha Creek Watershed District have and will continue to monitor the lake and more up-to-date information will be available in the weeks to come. The DNR will have a special page on their website dedicated to the Lake Minnetonka zebra mussel situation 9search ‘zebra mussel’).

Also as of this time, the agencies are exploring whether any kind of containment may be possible. The Lake Minnetonka Association will work with the agencies to explore all options. Again, more information will be forthcoming in the next month or two.

Typically, zebra mussel populations expand very slowly for the first two or three years, then multiply explosively.

Given this assessment and the way zebra mussel populations typically expand, I would expect the full impacts may take two to four years to be realized.

Zebra mussels will encrust hard surfaces – hard or firm lake bottoms, boat hulls, mooring buoys, inside mechanisms in boat motors, water toys, docks and lifts. Here are some precautions that should be taken.

At the end of the day, unfortunately, zebra mussels will be in Lake Minnetonka forever. So, we must learn to cope with them.

What should boaters and lakeshore owners do?

1. When swimming or wading, wear protective footwear to minimize cutting your feet, as zebra mussel shells are razor-sharp.

2. Remove irrigation intakes from the water and drain completely when not in use, as the immature forms will encrust the intakes and pipes.

3. If possible, keep your boat and motor completely out of water (when not in use) to minimize the encrustation of zebra mussels.

4. If it is not possible to store your boat out of water, contact a marina to inquire about protective paints and annual maintenance.

5. Run you boats long enough to reach operating temperatures. The immature zebra mussels are very sensitive to heat, so a hot engine will kill them as they are flushed through the cooling system. Drain all water reservoirs after each use.

6. Help prevent the spread to other lakes and rivers. If you take your boat out of Lake Minnetonka, thoroughly clean your boat and trailer inside and out and let it dry for at least five days. Scrape off any encrustations, wash with high pressure, hot water (120 degrees), then drain and dry all water reservoirs.

7. If you sell used docks, structures or water toys, be sure they are decontaminated and cleaned before they leave the area.

We expect zebra mussels will affect the overall health of the lake and the fisheries. As the infestation develops, agencies charged with managing Lake Minnetonka’s environmental health – MN DNR and the Minnehaha Creek Watershed District – will be reporting to the community.

I am saddened by this news, as I know all of you are as well. The Lake Minnetonka Association remains committed to being advocates for AIS prevention. While zebra mussels are here, there are dozens of other invasive plants, animals and pathogens coming toward of Lake Minnetonka.

Lake Minnetonka Association, Dick Osgood

Senator vows to deal with mussels

By: Amy Chaffins, Alexandria Echo Press

State Senator Bill Ingebrigtsen was in Alexandria Friday for an environmental issues meeting and it was aquatic invasive species – specifically zebra mussels – that took center stage.

Ingebrigtsen assured local members of the Minnesota Environmental Partnership that dealing with aquatic invasive species is one of his priorities, and, he said, he intends to direct legislation on the issue.

“It’s a serious issue that can’t wait until another session,” he said.

Ingebrigtsen is chairman of the Senate’s Environment and Natural Resources Committee. Plus, he sits on the Lessard Sams Outdoor Heritage Council – the Outdoor Heritage Fund is one of four funds created by the Clean Water, Land and Legacy Amendment and it receives one-third of the money raised by a sales tax increase.

“There is funding available to deal with this,” Ingebrigtsen said Friday. “That means some projects will have to be put on hold, there has to be some prioritization.”

Bonnie Huettl, president of the Douglas County Lakes Association (DCLA), said, “I think [the meeting] went well and I think he got the message. Now we have to see what happens.”

Members of several lake associations from across Douglas County also attended Friday’s closed-door meeting with Ingebrigtsen; one of their specific concerns is zebra mussel containment.

To contain them, Huettl said, the DCLA would like to see state funds used to close, or monitor, boat accesses to all infested lakes in the area.

“That way, boats coming out do not spread the mussels,” Huettl said.

Local lakes, known to be infested, with zebra mussels include: L’Homme Dieu, Carlos, Geneva, Victoria, Darling, Jessie and Alvin.

Commentary – Time is now to stop zebra mussels

By Bonnie Huettl, Alexandria, MN

We must stop the spread of aquatic invasive species (AIS), namely zebra mussels (ZM), in Minnesota waters and contain the spread from infested waters until an antidote is found, and we must do it now. The issue has been around since 1989 in Minnesota and the attitude of the DNR has been to not inform the public of the devastation zebra mussels can cause. They were not prepared to move forward with anything other than education (collateral) and signage while other states have programs in place. How sad! We can change that.

A grassroots movement has been started to make some swift and effective changes as to how the infested lakes are accessed. A meeting was held on Friday, February 4 with Senator Ingebrigtsen to let him know how important the issue is and to carry forward the message to the Legislature that citizens want something done now. More than 75 people attended this meeting so there is support here in Alexandria as well as other parts of the state. He got the message.

The DNR will make a presentation to the Senate Environment and Natural Resource Committee, which is planned for February 10 and Senator Ingebrigtsen chairs that committee. Their presentation will likely be similar to what was presented to the House Environment and Natural Resource Committee, which primarily outlined AIS prevention ideas from stakeholder meetings. The House chair, Representative Denny McNamara, directed comments to the DNR, telling them to put together a plan to stop the spread of AIS in the state of Minnesota and bring it back to this committee. Many funding options have been identified as possibilities, ranging from LCCMR (lottery) to Clean Water Funds, which became available in 2008 when Minnesotans voted in favor of The Clean Water Act. To this point, none of that money has been used to protect Minnesota lakes from such nasty invasives.

We can only hope that the DNR and legislators quickly agree on a plan that will boldly address the spread of zebra mussel infested waters by fishing opener. Yes, this will alter the way we use the lakes but so will the invasives. Change is difficult for some but change is what must happen.

The target for the “Band-Aid” plan is opening fishing 2011. Aggressive, yes, but we have lost precious time educating while they are spreading. To learn more about mussels, visit

Zebra mussels suspected in Argo Dam control system failure; divers on site for icy underwater work

Topics: Edward Vielmetti

Zebra mussels (Dreissena polymorpha) are suspected to be the cause of erratic water flows on the Huron River downstream from the Argo Dam. A team of divers from Solomon Diving in Monroe, Michigan, are on site Tuesday morning to go under the icy waters of Argo Pond and inspect the intake pipes that lead to the pond level sensor system that controls the dam. A failure of this control system last week led to over four days of erratic river levels (“Argo Dam control system fails, causing Huron River to rise and fall quickly,”, January 26, 2010).

The divers aren’t in the water yet, so it’s time to look at the zebra mussels—where they are now, how they got here, what they do and how to manage them when they arrive.

Where are zebra mussels from?

The zebra mussel was first described in the lakes of southeast Russia, and their natural distribution also includes the Black and Caspian Seas. They have a long history as an invasive species, and were successfully established in Great Britain (1824), The Netherlands (1827), The Czech Republic (1893), Sweden (1920), Italy (1973), the Great Lakes in the USA (1988) and California (2008). Long-distance transport to the United State and Canada was helped by the opening of the St. Lawrence Seaway, which allowed vessels from Europe to dump their ballast water into the Great Lakes.

A related species, the quagga mussel (Dreissena rostriformis bugensis), has followed a similar path. Where the two species are found, the quagga mussel tends to outcompete the zebra mussel and it grows in greater densities.

What do zebra mussels do to dams?

There’s nothing that a zebra mussel loves more than to attach itself to the inside of a pipe carrying fresh water. The mussels are filter feeders, drinking up to a quart of water per day and slurping up plankton from the water. When they die, the next round of zebra mussels attach themselves to the layer of shells below them, building up a thick crust of debris. The layers build up until the pipe is largely or completely blocked.

Dams are controlled by monitoring water levels on the impoundment above them. If the intake valve to the monitoring well is blocked, changes in water level will not be registered right away, and water level controls will be erratic. In areas where zebra mussels are plentiful, regular inspections and maintenance are required to keep intake valves clear.

Diving for zebra mussels

It’s not as glamorous as deep sea diving for pearls. Divers go underwater and inspect pipes and intake valves for clogs, and break through the clogs as needed to let water run free.

The City of Ann Arbor has contracted with Solomon Diving from Monroe, Michigan, for the Argo Dam dive this morning. They have been in the business of helping utilities control zebra mussel populations since the 1980s.

In the winter, of course, dive operations are much slower and colder; in general, you’d expect that a routine dam maintenance schedule would do this work in more temperate circumstances.

For further reading

Edward Vielmetti writes about the Huron River for

‘Up against a beast’

By: By Pippi Mayfield, Detroit Lakes Tribune, Alexandria Echo Press

Editor’s note: Because of the presence of zebra mussels and other aquatic invasive species in the Douglas County area, we think this story from the Detroit Lakes Tribune is noteworthy to local readers.

Is Minnesota becoming the land of 10,000 lakes infested with aquatic invasive species?

“We need to preserve the finest place on the face of the earth,” Representative Davis Hancock said.

“We are the land of 10,000 lakes, and we need to protect that,” Senator Rod Skoe agreed.

On January 15, officials from Becker, Hubbard and Otter Tail counties, legislators from various districts throughout Minnesota and concerned citizens filled the conference room at Minnesota State, Detroit Lakes to discuss the flowering rush and zebra mussel taking over area lakes and rivers.

Pelican River Watershed District (PRWD) Administrator Tera Guetter said the first invasive to hit Detroit Lake was curly-leaf pondweed.

“It’s more than just a nuisance,” she said, showing slides of mounds and mounds of the weeds washing up on the beach and other shoreline. She added that the PRWD spends about $150,000 a year in roadside pick-up of weeds in the summer.

Since then, there have been more invasives, most notably and most talked about now, flowering rush.

Invading the lakes

Flowering rush first came to the Detroit Lakes area when a lake resident “innocently planted it on the shoreline as a decorative plant,” Mayor Matt Brenk said.

Since then, it has spread to Curfman, Melissa and Buck lakes.

“This plant is not easy to drive through,” Guetter said. “It’s certainly not something you want in front of your house.”

When it first appeared in Detroit Lake a few years ago, Guetter admitted that the watershed district cut the weeds.

“It was the only thing we knew what to do. Unfortunately, it’s enabling the growth of the plant.”

The plant is so new, there is very little to no research available on it. The PRWD has contacted for two studies on the growth of flowering rush and the treatment of it. The Army Corps of Engineers is growing the plant in labs and trying various treatment methods. A study with a professor from the University of Mississippi and from Concordia College is studying the growth and ecology of the plant.

She said more than $1 million has been spent – in taxpayer money – for treatment of the plant thus far.

“Our citizens are very concerned and support us on this,” Guetter said.

The public voted in November to approve a 1 percent food and beverage tax, with a portion of the funds going to help finance the two studies being conducted. The studies are $150,000 total.

Detroit Lakes City Administrator Bob Louiseau said the city spent $50,000 in weed pick up in 2010. The city averaged a dump truckload a day, and on the heavy usage times, like Fourth of July for example, the city would pick up four truckloads.

Zebra mussels loom

On the horizon, the next big concern is zebra mussel. For neighbors though, it’s already ruining their lakes.

“Why didn’t someone do something earlier to prevent zebra mussel infestation?” Otter Tail County COLA President Shawn Olson said she thinks with Pelican Lake now infested.

She considers the day in 2009, when zebra mussels were first identified, as the Black Day, and in one year, the mussels have taken over the lake. And it has spread to Lake Lizzie, and Prairie Lake is next in the chain, she said.

Moriya Rufer, RMB Environmental Laboratories, described how zebra mussels attach themselves to hard surfaces – bottoms of boats, dock legs, minnow buckets, pipes, etc. – and are hard as cement and have to be scraped off.

Another threat to Pelican Lake, she added, is that the mussels will also wash up on the shore, and beaches will no longer be sandy but instead as sharp and hard as shells, a surface people won’t be able to walk barefoot on anymore.

It’s even more discouraging, she said, because the lake association has preventative programs in place, and Pelican Lake was still infested with zebra mussel. The invasive produces millions and millions of eggs each year, and the larva is so small, it can’t be seen, so it’s easy to unknowingly spread it.

Spreading any kind of invasive is easy.

According to a Star Tribune article, “about 62,000 trailered boats come and go every year from Lake Minnetonka, and those boaters end up visiting 257 other lakes, DNR officials say. Lake Mille Lacs has similar use. Between 65,000 and 100,000 boats use Lake Mille Lacs each year, and those boaters end up visiting 171 lakes.”

DNR involvement,


Louiseau said the city has tried to be proactive, applying for permits to treat the flowering rush while it is still pre-emerged, but that the permits are delayed so long that emerged plants were treated with pre-emergent chemicals.

Permits were also only given to treat the swimming beach area, a small portion of the infected area.

“I believe it’s time for the state of Minnesota to get involved,” he said, meaning financially and trying to get the Department of Natural Resources – the ones who grant permits – to cooperate more at the local level.

“We can’t accept this as status quo and learn to deal with it,” he said of the rush. “It’s critical that we work together on this.”

Control needs to be turned over to the local government agencies, Zorbaz owner and founder Tom Hanson said. It’s not money holding treatment back, but “horrendous bureaucracy,” he said.

“Let’s not just leave [the summit] with a good feeling and then a year later, nothing’s been done,” he added.

As a part of the DNR, Luke Skinner said there is an aquatics invasive species (AIS) prevention report coming out the end of January or first of February containing “ideas to determine the most important ideas for action that have support.”

He said that the stakeholders meetings produced information on AIS laws and the enforcement needed of those laws, increasing awareness, inspection process, focus on high-use infested waters and a possible increase in penalties.

In 2009, DNR officers spent 4,800 hours to AIS enforcement. In 2010, he said, that number jumped to 12,800 hours.

“Most [invasives] are spread through people and their behaviors,” he said.

Lake effects

“Water quality is so important to us,” Becker County Commissioner Barry Nelson agreed.

He said that 54 percent of land value in Becker County is directly related to the lakes.

In 1927, citizens changed the name from Detroit to Detroit Lakes to keep mail from going to Detroit, Mich., accidentally. Detroit Lakes Regional Chamber of Commerce President Carrie Johnston said that alone showed the town’s pride in its lakes.

It still shows nowadays, with the chamber adopting a “see you at the lakes” slogan to promote the area throughout the United States and Canada.

According to an Explore Minnesota Tourism 2008 study, Johnston said that 1,300 jobs in Becker County are in the leisure and hospitality industry. That industry generates $63 million in gross sales and $4 million in state taxes.

In 2007, Becker Counties’ 40 resorts had over $8 million in gross sales. Guess how many resorts are on lakes.

“The economic impact is huge in this area,” she said. “If the lakes aren’t [clean], we’re not going to see you at the lakes.”

“Unless we become more vigilant regarding this priceless asset, we will see our tourist dollars shrink, our real estate values decline and our quality of life deteriorate,” Hanson said.

When looking for locations to open a new Zorbaz restaurant – he’s opened 14 in 40 years – Hanson said that the No. 1 priority is the lake it is to be located on. The quality of the lake and its beach are imperative to the success of the business.

“Those are our gold mines, our oil fields,” he said of the lakes.

“I understand it’s a public asset,” Lake Detroiters Association President Howard Hanson said of the lakes, “but I believe local custodianship is most powerful kind.”

Dan Kittilson, Hubbard County COLA president, said that Hubbard County’s lakes haven’t been affected much yet – of the 40 lakes in the county, only four have curly-leaf pondweed and one lake and two rivers have faucet snails. But, that doesn’t mean it’s not concerning for Hubbard County.

“This is a shared interest,” he said. “Our lakes are shared by everyone.”

Lake users

By coming together, the group has a “better voice than the independent voice we may have,” Jeff Forrester, executive director of Minnesota Seasonal and Recreational Property Owners Coalition, said.

“Some claim that containing AIS is too hard, too difficult, too inconvenient,” he said. “If we do not stop the spread of AIS, local mitigation costs will soar, electricity and water treatment will become more and more expensive. Property values will decline, and fishing and recreational opportunities will be decimated. It is much cheaper to stop AIS than cope [with it] after the fact.”

Curtis Junt, a North Dakota resident, said even though he isn’t a resident of Minnesota, “this is the No. 1 place I want to be.”

The greatest resource is the lakes.

“Ninety-nine percent of our vacation budget went to your state. There is no other place on earth I’d rather be,” he said of the past years, bringing his family to Minnesota to vacation.

Chuck Johnson, a salmon fisherman from Perham, said he likes to fish Lake Michigan waters, but that lake is infested with quagga mussels, an AIS that is worse that zebra mussels, he said.

He warned legislators and the public that Minnesota has let these invasives infest the waters, and now everyone needs to pull together to prevent the next infestation.

Carl Towley said infestations isn’t anything new, and that if Minnesota truly wants to eradicate its AIS problems, the state needs to quarantine its lakes like other states like California, Colorado, Idaho and Arizona have.

“We’re up against a beast.”

It’s not just about education though, he added, something needs to actually be done.

“Education is good,” Lucy Johnson agreed, “but it’s too late for many of us with prevention only. We need intervention.”



“This is not a Democratic or Republican issue, it’s a Minnesotan issue,” Senator John Carlson said via a letter since he couldn’t attend the summit.

Skoe said he appreciates the local leadership and that DNR rules need to change. He also said Legacy Funds need to be used to help in funding these studies and treatments.

“We need a mindset change,” he said.

Representative Kent Eken said rather than the state wanting to acquire more land, it needs to focus on what it has and protect it.

“We’re not adequately taking care of the land we have.”

Representative Paul Marquart said when he met summit organizer Barb Halbakken Fischburg during his campaign for re-election, he heard for a good 40 minutes about AIS and her concerns.

“If we could bottle some of that passion, we’re going to be in a good stead for moving forward.

“I am not confident we can control this through education and enforcement.”

He said that if a man can be put on the moon, there has to be something to be done about aquatic invasive species.

Representative Bud Nornes said that the summit was very educational and “when you see it firsthand, it sinks in. I’m on board with whatever we can do to eliminate and eradicate.”

“This is an economic issue and a quality of life issue,” Marquart said. “We’ve heard your message loud and clear.”

Zebra mussels lose stranglehold on Hudson

NEW YORK, Jan. 21 (UPI) — Native mussels are beating back invasive zebra mussels in New York’s Hudson River, scientists say, although they’re not sure what is causing the turnaround.

Zebra mussels — striped, nickel-sized mollusks native to western Asia — first appeared in the United States in 1988 as stowaways in ship ballast water. Their tendency to starve out native invertebrates and foul equipment has made them serious aquatic pests, AAAS reported Friday.

Zebra mussels hit the Hudson hard in 1991, quickly gobbling up most of the river’s plankton while native mussels, clams, and other invertebrates plummeted to as little as 1 percent of their original populations.

“It looked really, really grim,” David Strayer of the Cary Institute of Ecosystem Studies in Millbrook, New York says.

Then around 2001, Strayer says, the native mussels stopped declining.

Researchers feared it was a temporary recovery, but the trend persisted, and in 2007 scientists reported a solid, albeit incomplete, comeback, although they’re not sure what might be driving it.

It could be native blue crabs or some other predator are eating more zebra mussels or their larvae, researchers say, or perhaps some undetected pathogen or parasite is keeping them in check.

The native invertebrates are approaching their pre-invasion numbers, scientists say.

Read more:

Zebra mussels in Lake Minnetonka

TOM MEERSMAN, Star Tribune

Zebra mussels have invaded Lake Minnetonka, a breach of the state’s defenses against invasive species that threatens to dramatically change the character of Minnesota’s 10th-largest lake within just a few years.

Department of Natural Resources biologists confirmed Wednesday that a small number of mussels are attached to rocks along the shore, and their size suggests that a reproducing population has been in the lake for at least a year.

In places where they’ve become established, the fingernail-sized mussels proliferate by the millions, consume food needed by fish, clog water intake pipes, ruin fish spawning beds and litter beaches and shallow areas with razor-sharp shells.

The mussels were found on the east side of Wayzata Bay near Hwy. 101. That’s not far from the lake’s outlet to Minnehaha Creek, raising fears that the mussels may spread into that waterway, or may have done so already. Minnehaha Creek is connected to lakes Nokomis and Hiawatha in Minneapolis.

For years DNR officials have worked with the Lake Minnetonka Conservation District and others to educate boaters and anglers to prevent the spread of zebra mussels. They also inspected boats and trailers and directed owners to remove plants, mussels and water from bait buckets and vessels that traveled in infested lakes and rivers. The efforts may have bought some time, but they didn’t stop the mussels’ entry into Minnetonka.

“Unfortunately, zebra mussels still found their way to the lake,” said Luke Skinner, supervisor of DNR’s invasive species program.

The discovery was dreaded news for Dick Osgood, president of the Lake Minnetonka Association, which represents about 600 lakeshore owners and businesses.

“This has been our fear all along, and keeping them out has been our top priority for the last ten years,” said Osgood.
Lake Minnetonka is the most heavily used lake in the state, he said, with an estimated 200,000 boats plying its channels, bays and open water annually.

With that amount of exposure, the discovery of mussels was not unexpected, said Osgood, but it was still a major disappointment.

“Bottom line is, I think they’re here to stay,” he said. “Not that we won’t do everything possible in rapid response, but I think it’ll change the lake forever.”

Osgood and representatives of the Minnehaha Creek Watershed District plan to do a quick assessment of the lake to see if they can find mussels in other places. There’s a chance, he said, that if they are only in one area, the mussels could be removed or killed before they spread further.

DNR officials said that the number of zebra mussels found was very low and that they would investigate the situation this week and beyond, including an extensive survey of the lake later this summer.

Osgood advocates limiting boat traffic in the infested waters, at least until the extent of the invasion is better understood.
In other places, he said, the discovery of zebra mussels is usually followed by 1 to 3 years of “lag time” in which a few more infested areas are found. At some point, usually about five years after the initial discovery, he said, the populations explode and the lakes start to change, sometimes unpredictably.

In some areas the numbers of different fish species increase or decrease, seeking a new balance as habitat and food sources change. Native mussels usually die out. And because zebra mussels constantly filter sediment and nutrients, water often becomes noticeably clearer.

That may please some, said Osgood, but it also means that light will penetrate deeper, boosting the growth of plants such as Eurasian water milfoil, an invasive that’s already a major nuisance and expense to control in Lake Minnetonka.

Resident spotted mussels

A local resident found the mussels in the lake early this week and reported them to the DNR. Skinner said that anyone else who finds mussels should contact the agency.

Zebra mussels are native to Eastern Europe and western Russia, and likely came to the Great Lakes in ballast water of ocean-going ships that traveled up the St. Lawrence Seaway. They were discovered near Detroit in 1988. Their first appearance in Minnesota was in 1989 in Duluth harbor, and they subsequently spread to 17 inland lakes, including Mille Lacs, Prior, and Le Homme Dieu and to portions of the Mississippi, St. Croix and Zumbro rivers.

Udai Singh, senior hydrologist and water quality specialist for the Minnehaha Creek Watershed District, said plans for what to do next are still very preliminary. If the mussels are firmly in the lake, he said, the district may install equipment at various locations downstream in Minnehaha Creek to check for them. The discovery in Minnetonka is “really unfortunate,” Singh said, and has already jump-started a new array of activities.

“Now since prevention is out the window, we will be more working in terms of control and management of them,” he said.
Tom Meersman •StarTribune