Statewide Phosphorus Multi-Discharger Variance

Phosphorus pollution in surface water has long been recognized as major contributor to harmful algae blooms and other water quality problems. In 2010, the Department of Natural Resources (DNR) took additional regulatory steps to curtail sources of phosphorus pollution. New requirements for point source dischargers under the 2010 phosphorus rule were found to result in economic hardship for many municipalities and industries that hold Wisconsin Pollutant Discharge Elimination System permits (WPDES permittees). The phosphorus multi-discharger variance (MDV) can extend the timeline for compliance with regulatory requirements for those WPDES permittees facing economic hardship. While covered under the variance, WPDES permittees optimize phosphorus treatment and contribute to nonpoint source phosphorus offsets.​

In 2014 and 2015, DOA undertook an analysis of compliance costs and resulting economic impacts associated with the 2010 phosphorus rule. The evaluation process is defined under s. 283.16(2) Wis. Stats. and required that DOA make a determination as to whether attaining the water quality standard for phosphorus is not feasible because it would cause substantial and widespread adverse social and economic impacts on a statewide basis. The final determination, dated 12/29/2015, found that water quality standards for phosphorus would cause substantial and widespread adverse social and economic impacts to the following statewide categories of dischargers: municipal treatment works, paper, aquaculture, cheese, food processors, and other industrial dischargers of process wastewater. Based on this determination, DNR sought approval of a phosphorus MDV from the US Environmental Protection Agency (EPA). The MDV was approved by EPA on February 6, 2017 for a 10-year duration. 

Pursuant to s. 283.16(3)(a), Wis. Stats., DOA must reevaluate the initial determination within 10 years of the above EPA approval date. To accomplish this, DOA and DNR will partner to prepare a report that reevaluates metrics used in the initial determination in light of current regulatory requirements, phosphorus treatment technology, and economic conditions. Following a public comment period, DOA, in consultation with DNR, will decide if the initial determination remains accurate. If the initial determination remains accurate, DNR will seek approval from the EPA for a renewed MDV for a time period beyond the current February 6, 2027 expiration date. 

​Download ​​the Report

State statute requires that DOA consult with permittees subject to water quality based effluent limitations for phosphorus and other interested parties in preparing the above-mentioned report. To this end, DOA and DNR have prepared a summary of currently available information for review by WPDES permittees and other interested parties. This information is the foundation for the report and determination. DOA will be accepting written comments on the document – please see further instructions within the document's introduction.​ 

Public Listening Sessions

Public meetings occurred in November 2023, to gain additional stakeholder perspectives. These listening sessions provided the chance for verbal comments relative to variance reauthorization. The meeting dates and locations were shared in advance with water quality stakeholders, WPDES permittees subject to phosphorus WQBELs, as well as being posted on the DNR’s Hearings and Meetings Calendar at ​​​​.

DNR Presentation for Listening Sessions​