icon for industrial stormwater
Caution: Much of the information related to industrial stormwater is outdated or can be readily found on the MPCA's website. As a result, we will be deleting or archiving much of the information related to industrial stormwater.
Information: Individual tables of Standard Industrial Classification (SIC) Codes have been deleted. The tables for all sectors (A through AC) have been compiled into a single .pdf document which can be found here: File:Standard Industrial Classification (SIC) Codes - Minnesota Stormwater Manual.pdf.
Information: Individual pages on stormwater requirements, guidance and sampling exceedance suggestions for each sector have been deleted. These pages have been condensed into a .pdf document which can be found here: File:Industrial stormwater requirements, guidance and sampling exceedance suggestions for each sector - Minnesota Stormwater Manual July 2022.pdf
Information: Individual tables of Industrial stormwater sector-specific benchmark values and effluent limits have been deleted. The tables for all sectors (A through AC) have been compiled into a single .pdf document which can be found here: File:Industrial stormwater sector-specific benchmark values and effluent limits - Minnesota Stormwater Manual.pdf

Industrial Stormwater 2020 permit issuance developments

Industrial stormwater: Permit development and program history We’ve been tracking suggested changes to the 2020 permit since the 2015 permit became effective. As of February 2019, here is our current list of drafted suggested changes and updated timeline. NOTE: these are subject to change. Updated tentative timeline as of 2/1/2019:

  • January – October 2018: Review existing permit language; sampling and other permit requirements. Draft list of suggested changes; compare EPA and Minnesota’s permit language"
  • November 2018 – January 2019: Draft changes
  • February 2019: Submit draft to MPCA legal staff for review. Draft fact sheet, “what’s changed?” document
  • March 2019: Prep document for public notice process
  • April 2019: Public notice draft permit
  • May – mid-June 2019: Review, respond to comments
  • June 15, 2019: Finalize permit language
  • June 30, 2019: MPCA commissioner approval
  • July 5 – October 5, 2019: Permittees apply for coverage. Permittees must apply 180 days before April 5, 2020
  • April 5, 2020: “New” permit is reissued and effective

If you have any suggested changes, or language you would like to see added or removed, please contact the industrial stormwater program by email or call: 651-757-2119. Emails are preferred for written documentation purposes.

General changes:

  • Getting the permit into a “Tempo-ready” format: One of the biggest changes has nothing to do with any changes to permit requirements. MPCA has a new agency-wide database called Tempo, and this general permit must be completely re-formatted to “fit” that new database. The entire permit will have language inserted into table format, one row per requirement. To see an example of a before-and-after stormwater permit, compare our Construction Stormwater 2013 general permit to the newly issued 2018 general permit.
  • Changing language to present tense, plain language: As we reformat the permit, we’re changing the language (not the requirements) to reflect active voice/present tense requirements, and trying to make the requirements easier to understand.

Part I

  • Authorization of discharges: For transferring coverage, remove “prior owner/operator” requirement; just have current owner and operator sign.
  • Clarity of vehicle washing prohibition: Within the limitations on authorization, add examples: 2. Domestic and industrial wastewater and process wastewater. For example, wash water, commercial equipment and/or vehicle cleaning.

Part III

  • Salt storage, salt management: BMPs for salt management: cover/store indoors, direct drainage away from receiving waters, reduce exposure when adding/removing from pile, and document salt pile location within SWPPP. Hired contractors must minimize use of salt.
  • Infiltration for all sectors: Review current requirements, compare to newly issued CSW permit, add additional requirements as necessary
  • BMP maintenance: Reduce time for installing backup BMPs from 7 days to 48 hours

Part IV

  • SWPPP modifications: If there are changes in personnel responsible in for any permit requirement, update SWPPP.
  • Annual reports: Add as new section (no additional requirements)

Part V

  • pH calibration: The Permittee shall maintain written records of all calibrations and maintenance of their pH meter within SWPPP.

Part VII

  • Remove: “Any additional” references within each sector “chapter” & Part 2 in each chapter; language is largely redundant to part 1 in each sector chapter.
  • Sectors J & L: 1+ Acres of CSW? Allow activities within the ISW permit and not require separate CSW permit
  • Sector J: Dewatering discharges aren’t allowed, remove phrase “dewatering or other process water”
  • Clarify requirements for sectors M and N
  • Sub-sector S3 definition: Changed to: “non-propeller aircraft departures”
  • Sector S: For those without de-icing activities, reduce sampling pollutants to just TSS, similar to Land and Water Transportation sectors. “Pending survey with results of the # of airports with no deicing/anti-icing fluid”

Appendix A

  • Anti-degradation review complete: no additional changes beyond what’s proposed above.

Industrial Stormwater Digital Document Library Digital Document Library

The Industrial Stormwater Digital Document Library provides guidance to help industrial stormwater facility staff meet the requirements of the industrial stormwater permit and assist with overall stormwater management. In addition to general guidance documents, the Digital Document Library has example documents that stormwater staff are using to manage their stormwater discharges. Common examples of documents in the library include:

  • inspection and checklists and forms
  • site plan review checklists
  • guidance documents & resources
  • standard operating procedures

All documents in the Digital Document Library are available for all site users to download and use. MPCA staff tries to ensure their compliance with the industrial stormwater prior to posting in the Digital Document Library Be sure to read the industrial stormwater permit to ensure you are in compliance with the permit requirements.

Industrial Stormwater Permit Information

Visit the Stormwater program for industrial activity webpage to learn about the latest requirements, training workshop information, permit reissuance details and more!

Industrial Stormwater Permit Information Access

Use this database to find detailed facility information about industrial stormwater facilities, including basic compliance information.

Industrial Stormwater Steps to Compliance


Other helpful information:

Technical guidance and information

Program contact information:

This page was last edited on 24 January 2023, at 16:56.