The Department of Natural Resources (DNR) began issuing new requirements for phosphorus concentrations in 2021, and municipalities were given several years to develop a plan to comply with the new limit. The Village of Grafton kicked off compliance planning in 2015 when they received a new discharge permit. Based on an evaluation of the wastewater treatment plant (WWTP), it was clear that optimization of the plant along would not be enough.
The Wisconsin Administrative Code outlines several approaches that municipalities can use to meet phosphorus removal requirements. Making improvements at the local WWTP is a popular option, but it tends to be expensive in terms of both capital and operating costs. Also, WWTP improvements may not actually lead to a clean river - the overall goal of phosphorus regulations.
Another approach, commonly called adaptive management, makes improvements within the watershed to reduce phosphorus runoff. Adaptive management recognizes that excess phosphorus in waterways comes from various sources. With a bird's eye view of phosphorus contributors, a wastewater discharger works together with agricultural producers, storm water utilities, developers, and other to improve water quality.
Adaptive management is a holistic approach that targets reducing phosphorus runoff while also supporting a clean Milwaukee River.
Learn more about the Village of Grafton's involvement with this innovative and money saving approach to meet DNR permit requirements here.