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The MPCA has developed a wastewater nitrogen reduction and implementation strategy with the goals of meeting the state nutrient reduction strategy’s goals and providing protections for aquatic life.

Beginning April 1, 2024, wastewater treatment facility designs must include the treatment units and hydraulic capacity necessary to achieve future nitrogen effluent limits.

Per- and polyfluoroalkyl substances (PFAS)

Municipal WWTFs are being requested to sign a memorandum of understanding (MOU) in relation to the first phase of the PFAS Monitoring Plan, which is part of Minnesota’s PFAS Blueprint.


Some NPDES permits will require that you submit a mercury minimization plan. These documents may helpful in preparing your plan.

Mercury minimization plan and sector worksheets

Priority Pollutant monitoring

Priority Pollutant monitoring is required as part of some National Pollutant Discharge Elimination System (NPDES)/ State Disposal System (SDS) permits. These reports have historically been submitted as PDF lab reports, the MPCA is now requiring that this data also be submitted in an electronic data deliverable (EDD) using EQuIS Lab_MN format. Use the following instructions to obtain the EDD in the LAB_MN format from your laboratory for submittal.

Salty discharge

Whole effluent toxicity (WET)

Measuring toxicity helps protect surface waters by measuring the toxic effect of an effluent directly for acute and chronic effects. NPDES permits that require WET monitoring must use the following test report forms when submitting WET data. These forms must be submitted electronically to the water quality submittal center at following the instructions located under Discharge monitoring reports.

Chronic toxicity

Acute toxicity

Labs performing WET analysis for NPDES permits

Compliance schedules and Protection of Water Quality Investment Act

MPCA must consider a municipality’s current debt load when developing a compliance schedule to meet a new effluent limitation (Minn. Stat. § 115.456). As a result, some basic financial information must be submitted as part of the municipality’s justification for a proposed schedule. Use the current debt load worksheet to submit this information to the MPCA:

Under the Protection of Water Quality Investment Act (Minn. Stat. § 115.455) a municipality that constructs a POTW to comply with a new or modified effluent limit, to the extent allowable under federal law, could be given a 16-year compliance schedule to comply with a new or modified effluent limit. Learn more:

Chemical additive approvals

Federal and Minnesota law prohibit chemical additive use in amounts that compromise aquatic life or waters protected for human health. If you use chemical additives, you must get approval from the MPCA and follow the procedures in the guidance and calculator documents. Information regarding banned or pre-approved chemical additives can be found in the Chemical additive review guidance. Get helpful tips and see a demonstration of the calculator in the videos linked below.

Water quality trading

Water quality trading is a market-based approach to the protection and restoration of surface waters, another tool to be used in conjunction with existing voluntary, regulatory, and financial assistance programs. Such market-based approaches offer flexibility to regulated entities. Learn more on the Water quality trading page.

Stormwater in NPDES/SDS wastewater permits

Stormwater from major municipal wastewater treatment plants and many types of privately owned facilities that process wastewater is considered industrial stormwater and must be permitted. The following compliance requirements and guidance are for facilities that have incorporated industrial stormwater permit requirements into their NPDES/SDS permit.

Starting with the 2022 annual report, you will submit online using an e-Service.

Spray irrigation

Municipal wastewater reuse

Water treatment plants

Wastewater from drilling