City of St. Paul – Stormwater Regulatory Guide for Proposed Development and Redevelopment Activities
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 St. Paul. 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. Applicable MWMO standards are evaluated by city staff. Compliance with MWMO standards is evaluated as part of the city’s project review process and is necessary to receive a city permit(s).
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 St. Paul are submitted to the City’s Department of Safety and Inspections and reviewed by a Site Plan Review Committee with input from the City’s Public Works Department and other relevant City departments, as needed. Staff from the City’s Public Works Department may coordinate directly with the applicant, as needed. Project proposers are encouraged to contact the City’s Department of Safety and Inspections and meet with the Site Plan Review Committee to discuss concept plans prior to submitting an application for site plan review.
MWMO Grant Program
Projects may be eligible for MWMO Capital Project Grants designed to fund stormwater management and/or habitat enhancements that fall outside of minimum applicable regulatory requirements for a project site. MWMO encourages developers to consider whether an MWMO capital project grant is appropriate for their project and contact MWMO staff for more information.
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 St. Paul 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; where city and MWMO language deviates, the city evaluates projects relative to both the city’s regulations and MWMO’s 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.
St. Paul’s Municipal Codes are available online; applicable chapters may include Chapter 52 Stormwater Runoff, Chapter 72 Floodplain 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: urban stormwater 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.