Statewide Phosphorus Multi-Discharger Variance
The multi-discharger variance (MDV) for phosphorus extends the timeline for complying with low-level phosphorus limits. In exchange, point sources commit to step-wise reductions of phosphorus within their effluent as well as helping to address nonpoint sources of phosphorus from farm fields, cities or natural areas to implement projects designed to improve water quality. The MDV is similar to an individual variance. However, multiple point sources can be covered under the MDV, whereas an individual variance only applies to a single facility. This provides for administrative streamlining and maximizes the potential benefits watershed projects may have through the variance program. The MDV factsheet [PDF] provides general information regarding this program. The Wisconsin Department of Natural Resources (DNR)'s Program Policy for Implementing Wisconsin's Multi-Discharger Variance [PDF] provides details about eligibility and implementation requirements for this program.
MDV Reauthorization
Wisconsin's phosphorus MDV was approved by the Environmental Protection Agency (EPA) on Feb. 6, 2017 and expires in February of 2027. The DNR is currently proposing to renew the variance to extend availability to 2035. The draft MDV package is available below, and is subject to a public comment period.
A hybrid public hearing is being held by the DNR to receive comments on the proposed multi-discharger phosphorus variance. This hearing will be held at 9:30 a.m. on Friday, March 21, 2025 at the DNR’s central office, Room G09, located at 101 South Webster St., Madison, WI 53703. Virtual attendees need to register on Zoom.
In addition to comments provided at the hearing, written comments also may be submitted to DNRphosphorus@wisconsin.gov or sent via U.S. mail to:
Wisconsin Department of Natural Resources
Permits Section – WQ/3
PO Box 7921
Madison, WI 53707-7921
The deadline for submitting comments is March 28, 2025. Written comments carry the same weight as comments provided at the hearing.
Documents Available for Comment
- County Payment Verification Form
- DNR Evaluation Checklist
- DOA Updated Economic Determination
- Evaluation of Nonpoint Source Phosphorus Reductions
- MDV Application for Industrial Facilities
- MDV Application for Municipal Facilities
- MDV Implementation Policy Document
- MDV Justification Document
- MDV Watershed Plan Checklist
- Supporting Document: Highest Attainable Condition Review of Wisconsin's MDV
- Supporting Document: MDV Phosphorus Letter from DOA to DNR
- Supporting Document: Phosphorus Economic Impact Analysis Reports and Addendum
Webinar recording
Learn about eligibility and process to achieve successful approval of a multi-discharge phosphorus variance.