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.
Draft 2024 WisCALM
WDNR has prepared an updated version of its WisCALM guidance; this guidance will be used to assess surface waters for the 2024 cycle.
This year’s updates include:
- distinction between biological thresholds and water quality criteria;
- new biological metrics (macrophytes, algae);
- new phosphorus biological response indicators (macrophytes, algae, diatoms);
- new oxythermal standards for Two-Story Fishery Lakes;
- new water quality criteria for PFOS and PFOA.
The draft guidance can be downloaded here: Draft 2024 WisCALM
A full record of changes can be downloaded here: 2024 WisCALM Change Log
Public Comment Period
A public comment period is being held on the proposed 2024 WisCALM updates. Public comments are open from Jan. 12 to Feb. 24, 2023.
Draft guidance can be downloaded by clicking on the following link: Draft 2024 WisCALM.
Comments can be sent to DNRWYWaterbodyAssessments@wisconsin.gov or via mail to Ashley Beranek, DNR, Bureau of Water Quality, 101 S. Webster St. WQ/3 Madison, WI 53707