The MPCA Municipal Separate Storm Sewer System (MS4) program developed the MS4 Implementation Guide to assist MS4 permittees in complying with the MS4 General Permit Minimum Control Measures (MCM) 1-6 permit requirements. This guidance package includes resources like example educational materials, written procedure templates, documentation templates, and model ordinances to support a Stormwater Pollution Prevention Program (SWPPP).

The MS4 Implementation Guide is available here: MS4 Implementation Guide

Additional MS4 guidance and resources can be found on the Minnesota Stormwater Manual MS4 home page

Please contact your assigned MPCA MS4 staff for questions.

The online Minnesota Stormwater Manual provides information about how to comply with Construction Stormwater and Municipal Stormwater (MS4) permits as well as providing information on how to keep stormwater clean. The stormwater manual wiki site will be decommissioned in October.

When this happens, the current URL for the manual (http://stormwater.pca.state.mn.us/) will be reassigned to the new stormwater manual website. The target date for this change is October 9th. 

As part of this effort, each page needs to be re-formatted to the new platform. All the manual pages will be available immediately. But there will be a time period where some of the pages are still in the old format and may not display properly. The MPCA will provide updates on the wiki home page as the switch date approaches.

When the switch occurs, stormwater manual content will no longer be available in the wiki format. The new platform offers improved accessibility and consistency with other MPCA websites.

Watch for training opportunities: MPCA staff will be scheduling several webinars in October and November to provide orientation to the new manual format, content, and resources.

The MPCA is continuing to work towards completing the updates to the Industrial Stormwater application services. The general permit and no exposure application service remains unavailable. The MPCA anticipates the service will be available in the coming months. Please watch for news about the application service on the Industrial Stormwater program’s webpage, via GovDelivery messages, or reach out to Industrial Stormwater staff. Applicants should plan to apply for permit coverage or no exposure certification as soon as the application service becomes available.

We encourage permittees to use this time to prepare for meeting the requirements of the reissued 2025-2030 Industrial Stormwater General Permit. Permittees must complete all necessary changes to a facility’s Stormwater Pollution Prevention Plan (SWPPP) prior to applying for permit coverage. Permittees should evaluate benchmark monitoring locations to determine if they’ve been correctly identified and properly placed to collect representative samples of runoff. Facilities with a Standard Industrial Classification (SIC) code listed in the permit’s Appendix D must prepare for per- and polyfluoroalkyl substances (PFAS) monitoring. This includes, but isn’t limited to, completing a PFAS monitoring plan and identifying the facility’s Area(s) of Concern (AOC) locations for PFAS. The 2025-2030 permit can be found on the Industrial Stormwater Program's webpage here: https://www.pca.state.mn.us/sites/default/files/wq-strm3-102g.pdf

The NPDES/SDS Construction Stormwater General Permit requires vehicle tracking Best Management Practices (BMPs) to be installed anywhere sediment can track out from the construction site or onto paved roads within the site.

Vehicle tracking BMPs must be installed in all these areas whether or not construction vehicles or residential traffic will be using these entrances/exits. If a road is fully closed to all traffic and no vehicles can exit, there is no need for a vehicle tracking BMP.

In addition to vehicle tracking BMPs, street sweeping is often required to help prevent sediment tracking onto the street. However, street sweeping alone can not be used as a vehicle tracking BMP—it must be used in conjunction with an established vehicle tracking BMP.

Stormwater ponds and other stormwater treatment practices function best and for longer periods of time when they include a pretreatment structure. A  pretreatment structure is a designated pool, sump, chamber, or other area that captures coarse sediment, larger particles, and trash that can fill up a stormwater pond too quickly.

We know little about how to best design pretreatment structures to reduce maintenance costs. However, a new project by the University of Minnesota will study how to design stormwater pretreatment systems to save pond managers time and money while keeping the water clean.

Researchers are looking for data from past or upcoming clean-outs. If you might have data to inform this project, reach out to John Chapman at chapm155@umn.edu. 

The Clean Sweep Program has released two new resources to assist with stormwater planning:

• New Planning Guide – Developing an Enhanced Street Sweeping Plan
• Updated Quick Estimating Tool – now with tailored calculations for enhanced sweeping to help you estimate cost of enhanced street sweeping, total mass of street sweeping materials, potential phosphorus removal credits, and staff time needed

The program plans to host virtual trainings for the tools this fall.

Looking for more resources and training to get you started?  Presentations and materials can be found on the Clean Sweep Program website.

The MPCA Smart Salting Training program partners with organizations across the state to host trainings. The winter maintenance trainings integrate science with practical strategies that save money, time, and environmental impacts by reducing salt use while keeping paved surfaces safe. The following trainings are open to the appropriate audiences and meet MS4 annual winter maintenance training requirements. For groups of 12 or more, consider hosting your own training and contact smartsalting.pca@state.mn.us.

For details on trainings visit the Smart Salting Trainings page.