County staff report progress on phosphorus, septic replacements and groundwater; RPC offers alternate population projection for land-use plan

Marathon County conservation and planning staff briefed the Environmental Resources Committee on April 1 about progress on several multi-year programs — including phosphorus reductions in the Fenwood Creek watershed, septic-system replacement work, a groundwater protection plan in development — and presented a working draft of Chapter 9 (land use) of the county comprehensive plan. The regional planning commission offered an alternative population-projection model the county may use for planning.

Fenwood Creek phosphorus reduction Conservation manager Kirsty Heidenreich reported that the Fenwood Creek pilot project has reduced phosphorus but remains short of the committee’s 2024 strategic-plan target. "We have reduced, we lehi to about a 13% reduction in the watershed, which is about 8,980 pounds of phosphorus," Heidenreich said, and noted the committee’s original goal was a 20% reduction (14,016 pounds). She cited funding constraints that limited the county’s ability to scale the incentive-based pilot across the whole watershed; staff plan further outreach and funding requests.

Septic-system replacement and maintenance Land resources manager Shad Harvey told the committee the county has replaced 835 failing systems from February 2018 through 2024. Harvey said the county currently tracks about 360 known failing systems remaining and anticipates that number may increase as more systems enter the county maintenance program and are inspected. "This year, we just finished getting the rest of our systems into our maintenance program," Harvey said; staff said maintenance inspections commonly reveal additional failing systems.

Groundwater protection and wellhead inventory Staff reported completion of the county’s groundwater sampling effort (roughly 1,000 samples) that will feed a groundwater protection plan the county expects to bring forward this year. Heidenreich said the county is compiling GIS layers of wellhead protection areas and recharge areas and described a pilot in the Village of Athens to convert cropland around municipal wells to prairie and perennial cover to reduce nitrate loading.

Budget and grants update The county finance director reviewed first-quarter fiscal-year 2025 general-fund and grants fund reports for Conservation, Planning & Zoning (CPZ), Parks, and Solid Waste. CPZ general-fund revenues year-to-date were reported at $1,810,009 (about 49% of budget) and expenditures at $595,433 (about 16% of budget) through March; grants are reported on a separate grants fund page. Parks and Solid Waste reports were described as within expected ranges for the first quarter.

Wisconsin Land and Water funding request Staff said Wisconsin Land and Water had asked county conservationists to present brief testimony to the Wisconsin Legislature’s Joint Finance Committee at a listening session in Wausau. According to staff, the statewide request discussed by Wisconsin Land and Water would seek $20,200,000 for county conservation staffing from the state; conservation director staff said they would appear and use a common script to support the request and invited committee members to attend the listening session.

Comprehensive plan — land-use chapter and growth projections Staff presented a working draft of Chapter 9 (land use) and sought committee input on data and projection choices. The Wisconsin Department of Administration (DOA) county population projections, released this year, show a decline in Marathon County population (the DOA figure cited in staff remarks was roughly a 5.5% decline across the projection period). The North Central Wisconsin Regional Planning Commission (RPC) provided an alternative projection used in a recent regional comprehensive plan: an approach that carries recent population growth rates forward, producing an alternative increase (staff cited a 15% increase in one example derived for the regional plan). Christian (RPC) said the RPC included both DOA projections and an alternative model in the regional plan "to provide counties with an option that reflects recent local growth trends." Committee members asked for documentation and staff agreed to follow up with RPC and provide the underlying numbers for committee review.

Why it matters: These reports influence county budgeting, conservation priorities, land-use planning, and grant strategies. Progress on water-quality targets and failing-system replacement affect public health and regulatory compliance.

Next steps: Staff will bring a groundwater protection plan later in 2025, provide additional detail on the comprehensive-plan population-projection options, and return to ERC with updates from the animal-waste work group and the Fenwood Creek outreach efforts.

Attribution: All program numbers, goals and staff statements are drawn from the April 1 ERC meeting transcript and staff reports presented on the record.