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Thanks to Rick Delaney for sharing this article with the MLA


State Of The Lake: Inside Lake Leelanau's Productive
Summer Battle Against Eurasian Watermilfoil
By Craig Manning | Aug. 30, 2023

Two steps forward, one step back: That old adage might just be the perfect way to
encapsulate where things stand in the war the Lake Leelanau Lake Association (LLLA) has
been waging against Eurasian watermilfoil (EWM), the extremely destructive invasive
plant species first found in Lake Leelanau waters in 2019.

According to Annalise Povolo, who serves as director of administration and programs for
the LLLA, the organization has had an immensely productive summer in combatting the
growth and spread of EWM. But not everything is rosy – especially given the fact that
recent climate change factors seem to be driving faster proliferation of EWM in Lake
Leelanau and the waters of other infected lakes.
“We've heard from other lakes that their EWM also had a really good year,” Povolo tells
The Ticker, noting that this past winter’s warm and mild weather proved extremely
favorable for the growth of the invasive plant. In a typical winter, inland lakes like Lake
Leelanau end up with cold waters and considerable ice and snow cover, which in turn
starves invasive plants like EWM for light and forces them to go relatively dormant.
Without a typical level of ice and snow cover, though, EWM “was able to grow more than
normal throughout the winter,” Povolo says.

All that growth meant the LLLA was fighting a different war at the start of the 2023 season
than it was last fall. At the conclusion of the 2022 field season, LLLA had hired a company
called Zero Gravity Aerial to perform a full drone survey of Lake Leelanau. “This survey
provided us with the precise locations of the EWM in the lake, from individual patches to
large infestations,” Povolo wrote in a recent newsletter. “Using this information, we set
out at the beginning of the [2023] season with a ‘plan of attack’ for our fight against EWM
with an artillery of tools.”

But that plan wasn’t calibrated to the wintertime growth, and a second survey by Zero
Gravity Aerial this past spring showed that the chessboard had shifted significantly during
the offseason. There was more EWM in more places, making it clear to Povolo and her
team that they were going to need to “kick it into high gear” and have an immensely
productive summer to beat back the creeping presence of this invasive species.
Fighting EWM has become the top summer priority for EWM this decade. The invasive
species was first identified in the south lake in 2019, and efforts at managing infested
areas began in earnest during the spring/summer season in 2020. Those management
efforts have grown each summer since, requiring more resources, more hands on deck,
and more investment from LLLA and its supporters.

Per Povolo, though, that vigilance is essential to save Lake Leelanau from the damage
that EWM could cause if allowed to run rampant. In her recent newsletter, Povolo wrote
that the invasive plant “can grow up to the lake’s surface, choking out native plants and
growing dense mats – making some highly infested areas impossible to swim in and drive
boats through.”

The good news is that, while the LLLA may have lost a battle to EWM over the winter, the
organization seems to be winning the war. Povolo reports that “two larger, previously
treated sites” of EWM in Lake Leelanau are now completely free of the invasive plant,
proving that it can be eliminated with the right tactics. She’s hopeful that this summer’s
record-breaking efforts from the LLLA team and its many volunteers will show even more
substantial gains come next season – even if the winter forces the organization to settle
once more for a “two steps forward, one step back” outcome.

LLLA has been able to eliminate EWM by covering up infestations with large
biodegradable burlap barriers. Those barriers – essentially big, sprawling burlap blankets
– cover over the plant and starve it of sunlight, disrupting the photosynthesis process for
long enough that the plants die off. As Povolo explained to the Leelanau Ticker last year
update-from-lake-leelanau/), this approach works because EWM has not yet
established a seed bank at the bottom of Lake Leelanau. In lakes with out-of-control EWM
infestations, the plant has been allowed grow to the surface, where it flowers and
produces seeds. Those seeds then sink to the bottom, establishing the kind of seed bank
that can perpetuate EWM even if the plants themselves are killed off. In Lake Leelanau,
native plants have seed banks but EWM doesn’t, which means that eliminating EWM
infestations opens up those areas for native plants to grow back.

In 2022, Povolo says LLLA was able to set 2.2 acres of burlap over EWM infestations in
Lake Leelanau – nearly 96,000 square feet. Already this year, the organization is up to
over four acres of coverage, and Povolo anticipates that, “by the end of this season, we
could almost double what we did last year.” Another drone survey this fall will offer some
clarity on how much progress LLLA has made.

When asked how LLLA was able to have such a record-breaking summer of anti-EWM
efforts, Povolo points to numerous factors. For one thing, favorable weather allowed
crews to notch more days out on the lake. For another, a veritable army of volunteers
came out to help with efforts this summer – including, on one day in July, more than 20
community members who assisted in laying down “1,200 feet of burlap, all in one line.”
A robust partnership with the Grand Traverse Band of Ottawa and Chippewa Indians has
been extremely valuable as well, Povolo adds, as has the financial support from the Keller
family, the local philanthropists who are funding LLLA’s “aquatic invasive species
remediation control and prevention efforts” on a three-year basis, from 2022 to 2024.

That financial support meant LLLA this summer was “better equipped than we had ever
been in previous years,” per Povolo, with three boats dedicated to EWM remediation, a
full-time seasonal technician “to drive our boats and prepare materials,” more biologists
on staff to lead the efforts, and more SCUBA divers “than we had ever employed” to take
care of actually laying the burlap over the EWM infestations.

Povolo is hopeful that the LLLA will be able to hire even more divers to expand its EWM
remediation efforts in future years – a goal that could be helped by the creation of a
brand-new charitable foundation. That foundation, called Friends of Lake Leelanau, will
eventually take the baton from the Keller family to fund LLLA’s fight against invasive
species. Povolo tells the Leelanau Ticker that Friends of Lake Leelanau is currently setting
up an endowment with the goal “to have it up and running by January 1 of 2025.”
“At that point, LLLA will apply for grants from Friends of Lake Leelanau, who would then
award us the grants from the money that has been raised in that endowment,” Povolo

A great article from the current issue of the Michigan Lakes and Streams Associations magazine, Michigan Riparian, reprinted with their permission. Now that the ice is breaking up, there is always some shoreline repair work to do.  Now is a good time to think about options to soften our shoreline. This article explains why seawalls and hard shorelines are bad for the lake and what better options exist. We have many great resources here in Kalkaska County to help.



Seawalls and hardened shorelines significantly degrade lakes by reflecting wave energy, eliminating shoreline habitat for
fish and wildlife, promoting runoff of nutrients and pollutants, and degrading water quality. The individual and cumulative impacts of seawalls on our inland lakes have been significant, with the National Lakes Assessment indicating that over 50% of Michigan’s lakes have degraded lake habitat complexity and lakeshore habitat.

Seawalls and hard armoring on inland lake shorelines don’t allow for the absorption and dispersal of wave energy. Because armored shorelines reflect wave energy, they can make erosion worse in other areas. Additionally, hard armoring fragments the land-water interface and results in a loss of habitat complexity. The nearshore zone plays a critical role in the various life cycles of many invertebrates, amphibians, and fish, providing spawning and nursery areas, refuge, and foraging opportunities, as well as other functions. In addition to habitat, healthy littoral zones and shoreline plants stabilize sediment,
reduce turbidity, absorb wave energy, and provide increased ecological integrity. The loss of nearshore littoral habitat has been shown to adversely affect fish and wildlife, and to negatively influence recreational fishing on lakes. The effects of individual shoreline developments on the nearshore lake environment accumulate over time, affecting fish, amphibians, birds, and other wildlife.

Bioengineered shoreline stabilization includes techniques that can prevent erosion, as well as improve water quality, and fish and wildlife habitat. Shoreline protection techniques that use deep-rooting native plants and shrubs, in addition to biological erosion control structures, natural materials, coir logs, brush bundles, and rock to protect shoreline as well as add habitat, are a best management practice on inland lakes in Michigan. These techniques can be designed in such a way to be able to handle a variety of conditions and water levels. Using plants in the littoral zone and biological materials to disperse wave energy, rather than reflect wave energy, is crucial to protect your property and your neighbor’s property. In the State of Michigan, the loss of lakeshore habitat and lakeshore complexity are major stressors on our lakes. Activities
that simplify the shoreline, such as eliminating aquatic and emergent vegetation, seawalls, and fills into the littoral zone, result in lower diversity as shoreline and aquatic plant and animal species are eliminated. Diverse natural ecosystems are better able to cope with stress because there are a variety of species that thrive under different conditions. Maintaining
habitat complexity on our inland lakes perpetuates the functions and values we all enjoy.


EGLE recently updated the General Permit and Minor Project Categories for wetlands, lakes, and streams in Michigan. The General Permit and Minor Project Categories are expedited permits for activities which will cause only minimal adverse effects when performed separately, and will have only minimal cumulative adverse effects on the environment by incorporating current best management practices (BMP). For shoreline stabilization projects, using bioengineering techniques, including plants, rocks, and woody structures are the current best management practices. These BMPs protect shorelines from erosion while also protecting and enhancing the water quality and habitat of our inland lakes. We’ve
reached a point in Michigan where the education, technology, and infrastructure has made less impactful alternatives widely available and achievable. We know that there are many owners with existing seawalls who apply for replacement of those walls every year, and the new category allows for replacement of existing seawalls if BMPs are incorporated. The
category is flexible, giving applicants the ability to choose the BMP that they prefer, or to propose another measure of their choice.

The choices include:

  •  Reduce the total length of the seawall by 25% or more, and use
    riprap or bioengineering on the remaining area. For example, this could
    include a break in the wall for bioengineering, or a shortened wall at one
    end, etc.
  • Shoreline woody structure waterward of the replacement wall.
    Designs following the protocol from the Wisconsin DNR's document
    entitled, "Fish Sticks; Improving Lake Habitat with Woody Structure" are
    recommended. We will share a link to that document in The Michigan
    Riparian magazine's companion newsletter. 
  • Maintenance of a minimum 6 ft. wide no-mow zone or native planted buffer strip landward
    of the wall, for the entire length of the wall. It may include minimal breaks
    for riparian rights access, such as around docks or swimming areas.
  • Other measures approved by staff.


  •  Seawalls cause scouring of the lake bottom and erosion of
    neighboring properties, but BMPs such as shoreline woody structure,
    riprap, and bioengineering address this impact by absorbing and
    dissipating wave energy.
  •  Seawalls cause sediment and nutrient suspension, and cumulatively
    lower water quality, but BMPs such as natural buffer strips, shoreline
    woody structure, riprap, and bioengineering address this impact by
    filtering sediment from runoff and stabilizing sediment.
  • Seawalls do not support aquatic and shoreline vegetation growth,
    but bioengineering and shoreline woody structure BMPs address this
    impact by dissipating wave energy and supporting plant growth.
  •  Seawalls have no habitat complexity or ecological value, but BMPs
    such as riprap, shoreline woody structure, and bioengineering address
    this impact by creating more complex microhabitats where organisms
    can thrive.
  • Seawalls create a barrier for animal movement, but BMPs such
    as reducing seawall length and  bioengineering address this impact by
    improving land-water connectivity.


These criteria allow a permit to be issued under an expedited category, and do not require financial assurance, easements, or detailed monitoring efforts. There are many resources available for lakefront property owners to find contractors and learn about different options for shoreline stabilization. EGLE recently gave a webinar covering BMPs for inland lake shorelines including the seawall replacement category and BMP requirements.

This is the last lake level I will report for 2022. Data as of 10/18/22. Some rain has helped bring the level up a bit. A good snowy winter should replenish us in the Spring.



Manistee Lake

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