Sustainability Board recommends updated Chapter 14 standards to address stormwater pollutants

The Oshkosh Sustainability Board voted unanimously June 2 to recommend a set of updated post-construction stormwater water-quality standards for Municipal Code Chapter 14 aimed at reducing sediment and phosphorus in local waterways.

The vote followed a consultant presentation on options tied to the Wisconsin Department of Natural Resources's total maximum daily load (TMDL) work for the Fox and Wolf watersheds and a citywide analysis of how different practices and numeric targets would affect new development and redevelopment across the city.

Board members said the recommendation seeks a balance between achievable on-site practices and the city's responsibility to make measurable progress under state watershed goals.

Consultant Chuck Behm, who led the analysis on behalf of the city, described how the TMDL sets reduction targets for total suspended solids (TSS) and total phosphorus (TP) and how technology and land availability affect those targets. "We do expect that the target reductions from this TMDL study will be rolled into that [the next municipal permit]," Behm said, referring to the city's stormwater permit. He stressed that phosphorus is harder to remove than sediment because a larger share is dissolved in runoff rather than bound to particles.

City Department of Public Works staff told the board the technical threshold that typically triggers on-site…