This guide provides the information needed to understand and carry out the MWMO’s member cities’ stormwater requirements. Use the Find Your Watershed tool to confirm your location within the MWMO and the City of Minneapolis. The information below does not apply if your project is not within the MWMO.
The MWMO is not a permitting entity and no permit is required from the MWMO. City standards are aligned with MWMO standards. Compliance with City standards is evaluated as part of the city’s project review process and is necessary to receive a city permit(s). Projects in compliance with City of Minneapolis standards are considered in compliance with MWMO standards.
Additional (non-stormwater) city and state requirements, and associated permits, may be applicable to your project (e.g., NPDES construction permit). The developer is responsible for securing all applicable permits related to their projects.
City Review Process
Proposed land-disturbing activities in the City of Minneapolis are reviewed by the City’s department of Community Planning and Economic Development (CPED) with input from the City’s Public Works – Surface Waters and Sewers division (PW-SWS) and other department staff, as needed. Project proposers are strongly encouraged to contact CPED prior to submitting a permit application (and supporting documentation) to determine the need for initial planning meetings.
Stormwater Regulations
The city and MWMO have worked together to align the MWMO’s non-regulatory standards with the city’s stormwater regulations. Proposed land-disturbing activities located within the City of Minneapolis and within the MWMO must meet the city’s stormwater regulations summarized in this table. City stormwater regulations are presented alongside the corresponding MWMO standard. City standards are consistent with applicable MWMO standards. The city evaluates projects relative to City regulations; projects in compliance with city standards are considered in compliance with MWMO standards.
The table also includes definitions and links to modeling software and tools commonly used to demonstrate compliance with stormwater performance requirements. Developers should confirm the acceptability of any modeling or assessment tool with the city.
Minneapolis’s Municipal Codes are available online; applicable chapters may include Chapter 52 Erosion and Sediment Control and Drainage, Chapter 54 Stormwater Management, and others depending on the specific nature of the project. Note that projects disturbing more than one acre are also subject to the Minnesota Pollution Control Agency’s NPDES Construction Stormwater Permit.
Description of Stormwater Evaluation Applicable Tools
HydroCAD: tool used by Civil Engineers to complete hydrology and hydraulics modeling and analyses. CAD stands for Computer Aided Design.
MIDS calculator: tool available through the MPCA for estimating stormwater runoff volume reductions for BMPs based on MIDS performance goal (1.1 inches of runoff off impervious surfaces) and annual pollutant load reductions for total phosphorus. MIDS stands for Minimal Impact Design Standards (MIDS).
Minnesota Stormwater Manual: stormwater manual available in wiki format through the MPCA, designed to be user-friendly and flexible; manual includes stormwater concepts and stormwater management, stormwater issues, stormwater control practices (Best Management Practices), regulatory and permitting information, models, calculations, methodologies, pollutant removal, and credits, communications and outreach, and stormwater research and education information.
NPDES Construction Stormwater Permit (Minnesota): authorization to discharge stormwater associated with construction activity. The state of Minnesota, on behalf of its citizens through the MPCA, authorizes permittees seeking coverage under this general permit to discharge stormwater associated with construction activity to waters of the state of Minnesota. The goal of this permit is to reduce pollutant levels in point source discharges and protect water quality in accordance with the U.S. Clean Water Act, Minnesota statutes and rules, and federal laws and regulations. NPDES stands for National Pollutant Discharge Elimination System. In Minnesota, the MPCA regulates the federal NPDES Stormwater Program, which is part of the Federal Clean Water Act, as well as the related State Disposal System (SDS) permit program.
P8: model developed by William W. Walker, Jr., Ph.D. and Jeffrey D. Walker, Ph.D. (originally for USEPA, Minnesota PCA and Wisconsin DNR) for predicting the generation and transport of stormwater runoff pollutants in urban watersheds and predicting runoff and pollutant removal at user defined stormwater BMPs through processes of sedimentation, filtration, and infiltration. P8 stands for Program for Predicting Pollution Particle Passage through Pits, Puddles, and Ponds.
SWMM: free windows-based desktop program from United States Environmental Protection Agency modeling tool for planning, analysis, and design related to stormwater runoff, combined and sanitary sewers, and other drainage systems. SWMM stands for Storm Water Management Model.
WinSLAMM: urbanstormwater quality model developed by PV & Associates, LLC that evaluates runoff volume and pollution loading for each source area within each land use for each rainfall event and is used for evaluation green infrastructure.