Grindstone Lake Association

2019 Grindstone Lake Planning Workshop

PROTECTING GRINDSTONE LAKE THROUGH BETTER CITIZEN-AGENCY COLLABORATION

With the support of a Wisconsin DNR planning grant, GLA held a one-day workshop in July, 2019, to identify lake management priorities and how to achieve them through citizen-agency collaboration.  A total of 22 lake homeowners, GLA board members, or relevant state, county, and tribal agency officials discussed the current state-of-the-lake and the need for enhanced lake protection efforts. GLA participants represented all areas of the lake. 

FINDINGS

State and tribal experts described the current state of Grindstone Lake regarding its fishery, its water quality, and the threats from aquatic invasive species.  Click on the categories below to learn about our key findings:

Water Quality

  • Water clarity, specifically Secchi Disk depth, has decreased over the past 25 years by an average of 4 inches per year (based on a statistically significant trend analysis);
  • Other water quality parameters (Chlorophyll-A and Total Phosphorus) have varied from year-to-year, but no statistically significant trend has been identified in the data;
  • Phosphorus loadings to the lake are key factors in algal blooms and water quality;
  • Site specific criteria for phosphorus concentrations may be necessary to protect the dissolved oxygen-temperature habitat (two-story waters) in the lake.

Fishery

  • Climate change is having a significant effect on the lake;
  • Walleye and smallmouth bass fish populations are healthy in the lake and are reproducing naturally;
  • Shoreline and habitat protections could improve both populations;
  • Muskellunge populations are declining;
  • The two-story fishery in Grindstone including Cisco is under threat as climate change increases water temperatures and dissolved oxygen decreases with algae and plant decay.

Aquatic Invasive Species

  • Three aquatic invasive species are present in Grindstone Lake:  curly leaf pond weed; Chinese mystery snails, and rusty crayfish;
  • Eurasian water milfoil is present in Lac Courte Oreilles near to the entrance to Little Grindstone;
  • Aquatic invasive plants are transported between lakes on propellers, in live well waters, and bilge water;
  • Greater involvement of volunteers and paid workers at boat landings could help prevent introduction of invasive species into Grindstone Lake;
  • Management of lake water levels through the Billy Boy dam could be an effective tool in preventing aquatic invasive introduction to Grindstone Lake by boat transport directly from Lac Courte Oreilles.

In addition, we heard about the DNR Healthy Lakes grant program that could provide significant funding to address nearshore land activities that may be contributing phosphorus to the lake through financial and/or technical assistance.

The GLA Board works very hard to protect the lake, but desperately needs more volunteers for boat launch monitoring, aquatic invasive species monitoring, and land protection.  

Following these presentations, participants developed a list of key challenges for Grindstone Lake.  The three key challenges identified by vote of the workshop participants were:

  1. Mitigate phosphorus in the lake
  2. Prevention of aquatic invasive species
  3. Greater engagement of lake property owners in efforts to protect the Lake

ACTION PLANS

In the second part of the workshop, participants developed causes, solutions, and potential citizen and agency action for two solutions to these three key challenges.  Detailed plans for lake homeowner engagement, aquatic invasive species prevention, and phosphorus mitigation.

Conclusions

Several “next steps” were identified by the end of the meeting.  

1.  A volunteer has offered to serve as the communication leader for the Grindstone Lake Association to coordinate messaging and materials for the GLA website. 

2.  New signage is needed at either end of Little Grindstone to prevent AIS spreading into Grindstone from LCO and to remind boaters of the “no wake” zone in Little Grindstone.  This last point is especially important for waterfowl (e.g., loons) who nest in the area and cannot tolerate high waves from boat wakes.

3.  GLA will pursue state funding through DNR for shoreline protection (Healthy Lakes Program) and needed planning and data gathering efforts for lake management implement grants (Large-scale lake planning grants).  

If you are interested in volunteering for this summer’s lake protection efforts, please email us.

If you are interested in getting more details about the workshop, you can read the final report.

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