Our 2026 Management Plan

For the 2026 season, the MFA is pursuing a targeted herbicide treatment of approximately 40 acres across five areas of the Flowage where EWM beds are most established and where treatment has not occurred in at least three years. The five treatment zones — DNR Landing/SNC, ChantoCran-Bay, North Basin South, East Shore, and Southeast Bay — were selected based on the 2025 bed mapping survey, depth profiles, and professional applicator assessment.

Treatment Zone	Acres	Avg. Depth
DNR Landing / SNC	14.49	5.0 ft
East Shore	8.75	6.0 ft
North Basin South	6.29	6.5 ft
ChantoCran-Bay	6.05	6.0 ft
Southeast Bay	4.42	8.0 ft
Total	40.00	—

The Proposed Treatment

The MFA filed its herbicide permit application with the Wisconsin DNR in February 2026 and is currently awaiting review. The permit has been submitted with all required documentation, public notice has been published, and a licensed professional applicator has been engaged. We are cautiously optimistic about approval. If the permit is granted, treatment would proceed this summer under professional supervision, with post-treatment monitoring to document results.

This treatment is intentionally targeted — not a whole-lake approach — for two reasons. First, a focused treatment in areas with the heaviest, longest-established beds allows us to demonstrate measurable results. Second, it is the most responsible use of limited resources: directing treatment where the science says it will have the greatest impact.

What Effective Management Actually Costs

Since fall 2025, the MFA has consulted with aquatic biologists, DNR-licensed herbicide applicators, mechanical harvesting contractors, and lake management scientists to develop realistic cost estimates for the full range of treatment options available on the Flowage. The numbers are significant — and worth sharing plainly.

The spring 2026 herbicide treatment currently before the DNR is estimated at approximately $67,000, covering professional application of ProcellaCOR across the five target zones and the required water concentration monitoring that follows. Should a second treatment of the larger Serenity Bay and North Basin areas proceed later this season, applicator costs alone could reach $80,000 or more — figures that are preliminary but grounded in current market rates for a water body of this size and complexity.

Mechanical harvesting, which does not require a permit and can be deployed more flexibly, runs approximately $2,500 to $3,500 per day. A targeted harvest of the south shore of Serenity Bay — roughly 11 acres — would represent between $10,000 and $18,000 in contractor costs. It is a meaningful tool, but one that addresses symptoms rather than root cause; regrowth typically resumes within a season.

A winter drawdown remains in the MFA's toolkit as a contingency option — one we would pursue if herbicide permitting encounters serious regulatory obstacles. We want to be candid, however, that drawdowns generate real concerns among local stakeholders and affected property owners, and we are committed to exhausting other options first. If it ever becomes necessary, reimbursing the power company for the revenue impact of reduced water levels would cost approximately $32,000 before planning, permitting, and survey costs are added.

Regardless of which treatments are pursued in any given season, certain baseline costs recur every year: annual EWM bed mapping surveys run approximately $14,000, and post-treatment plant community assessments — needed to document whether a treatment is working and plan the next steps — cost roughly $4,400 per event.

Taken together, a single active treatment season on the Flowage can easily exceed $100,000. That figure is not meant to discourage — it is meant to orient. The members of Cranberry Lake, our neighbors to the east, have shown what is possible when a lake community commits to sustained, annual investment in their water. Their example is one we admire and intend to follow. The Save the Flowage campaign exists to build precisely that kind of financial foundation — not just to fund this season's treatment, but to position the MFA to act decisively whenever the Flowage needs us, year after year.

Whatever the Outcome

Whatever the outcome of the current permitting process, the MFA is committed to pursuing the most effective management options available. Lake associations that achieve lasting results do so by adapting their approach, maintaining community support, and sustaining the financial resources to keep working the problem year after year. That is precisely what the Save the Flowage campaign is designed to enable — and why your support matters regardless of what any single season brings.

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