Marshfield council approves $58,300 increase to design budget for Braine Park wet detention basin

The Marshfield Common Council on Jan. 28 approved a $58,300 increase to the 2025 budget to complete final design for a wet detention basin at Braine Park, Finance Director Jennifer Salinski told the council.

Salinski said the city's 2023 stormwater management plan recommends wet detention ponds to meet forthcoming phosphorus-reduction requirements. "Design is expected to be completed in 2025, and construction is expected to be completed in 2026," she said. The project already has a $150,000 Department of Natural Resources grant and is a candidate for a Clean Water Fund loan that could include 25% principal forgiveness, Salinski said.

The council's action increases the project budget by $58,300, funded by borrowing; Salinski recommended reducing planned borrowing for the street seal coat and crack-filling program by the same amount, saying that program has unspent prior-year funds to cover needs. Salinski gave an estimated full project cost of roughly $940,000 before applying grants and loans.

Alderman Tompkins pressed staff about long-term costs and whether the city's earlier $17 million estimate to comply with stormwater requirements remains reasonable. Salinski said the total will "most certainly go up," and that the Braine Park project likely exceeded the initial budget by several hundred thousand dollars. She added that a stormwater utility would place these costs on runoff contributors through fees rather than property-tax-supported borrowing.

Alderman Bridal asked whether the ponds are functional stormwater ponds rather than recreational features; Salinski replied, "Correct." The motion to approve the budget resolution was made by Alderman Tompkins and seconded by Alderman Giles. The clerk recorded at least Mrs. Spiros and Mr. Bridal voting in the affirmative; the motion passed.

The council is advancing design work so the city can apply for and, if awarded, draw down state funding and loan forgiveness that typically apply after projects are underway or complete. Salinski said staff expects to complete design in 2025 and construct the basin in 2026.

Planning for additional stormwater infrastructure is part of a multi-year effort the city will continue as state phosphorus rules take effect.