Wisconsin’s Consolidated Assessment and Listing Methodology (WisCALM)
Every two years, Sections 303(d) and 305(b) of the Clean Water Act require states to publish a list of all waters not meeting water quality standards and an overall report on surface water quality status of all waters in the state. To assess surface water quality throughout the state Wisconsin's Consolidated Assessment and Listing Methodology (WisCALM) guidance document is updated every two years. WisCALM provides guidance on the assessment of water quality data against surface water quality standards and for Clean Water Act reporting on surface water quality status. WisCALM updates are given to the public for their review before the guidance is finalized. Once finalized, the guidance is used in the current assessment cycle.
Current 2026 WISCALM
The Wisconsin Department of Natural resources has finalized its updates to WisCALM guidance for the 2026 cycle. This cycle’s updates included important details on using aquatic plants, E. coli and PFOA/PFOS to assess waterbodies, updates to terms, and a number of clarifying corrections. A full list of changes may be found under “2026 Version Updates” on page 2.
A public comment period was held from March 26th to April 24th, 2025. A response to comments is available here: WDNR Responses to Public Comment on 2026 WisCALM. The compiled comments are available here: 2026 Public Comments on Draft 2026 WisCALM.