Stormwater and impaired waters

National Pollutant Discharge Elimination System (NPDES) stormwater permits in Minnesota provide requirements for permittees that own or operate Municipal Separate Storm Sewer Systems (MS4s) that have approved Total Maximum Daily Load (TMDL) Wasteload Allocations (WLAs). This web page contains guidelines, guidance and training materials designed to assist stormwater permittees, TMDL writers and others who are working on stormwater-TMDL issues.

* Note: The following documents on this page have not been updated to reflect changes associated with the 2013 Construction Stormwater General Permit and 2013 MS4 General Permit.

Guidelines

MS4 Municipal Stormwater

Guidance

Training and outreach

We are in the process of developing a communication plan that includes outreach on a number of topics. Specific dates and places for these outreach events have not been determined. Topics to be covered include:

Impaired water and TMDL language and concepts in the 2011 permit (winter, 2010-2011).

  • Overview of impaired water language and requirements for the new MS4 permit — April, 2012.
  • Training workshops — reporting for the new MS4 permit. Starting in late spring/early summer of 2012, MPCA will offer three, half-day sessions intended to help permittees understand how to report on TMDL requirements in the permit. The sessions will be held in St. Paul, Rochester and Brainerd.

Watershed outreach. We intend on meeting with permittees at a watershed scale to discuss impaired waters and TMDLs affecting the permittees. Meetings will occur at the major watershed scale outside the Metro, and at the WMO level within the Metro. Topics will include updates on impaired waters and TMDLs within the watershed and linking TMDL implementation plans or other documents to MS4 permit requirements. We are currently conducting the following pilots:

  • Cannon River watershed — have met with representatives from regulated MS4s and developed language for the Cannon River watershed strategy document. We will meet with permittees to discuss linking implementation plan/watershed plan language with permit requirements.
  • Shingle Creek pilot to evaluate linkage between the Cedar Island, Pike and Eagle Lakes Excess Nutrient TMDL implementation plan and MS4 permit requirements.

We will continue to have our annual meetings in the spring. The spring 2012 meeting will focus on the new MS4 permit.

Training modules are designed as training tools for a variety of audiences.

Industrial stormwater

In 2010, the MPCA re-issued the NPDES/SDS General Stormwater Permit for Industrial Activity. To meet federal and state requirements for impaired waters, the permit includes new requirements for impaired waters covered by a USEPA approved TMDL. The revised permit may be found on the MPCA Industrial Stormwater web page.

MPCA guidelines for setting TMDL Wasteload Allocations for permitted industrial activities can be found at PDF icon MPCA Stormwater TMDL Guidelines for Setting Wasteload Allocations.

Construction stormwater

In 2008, the MPCA re-issued the NPDES/SDS General Stormwater Permit for Construction Activity. To meet federal and state requirements for impaired waters, the permit includes new requirements for impaired waters covered by a USEPA approved TMDL. The revised permit may be found on the MPCA Construction Stormwater Web page.

MPCA guidelines for setting TMDL Wasteload Allocations for permitted construction activities: PDF icon MPCA Stormwater TMDL Guidelines for Setting Wasteload Allocations.

Project status

The following spreadsheets provide summaries of impaired waters and TMDLs for regulated MS4s. The spreadsheet includes several worksheets that summarize approved TMDLs, on-going TMDLs, TMDL approval dates, a list of impaired reaches, and more. This document will be updated in the spring and fall each year. This will be updated every May and November.

  • PDF icon Wasteload allocations for MS4s - a summary of approved TMDL WLAs for regulated MS4s, last updated November, 2010. This includes EPA approval dates. (wq-strm7-33a)
  • PDF icon Future WLAs for MS4s - a list of MS4s that will receive WLAs in on-going TMDLs once the TMDL is approved, last updated November, 2010. (wq-strm7-33b)
  • PDF icon On-going TMDLs - a list of TMDL studies that have been started but for which MS4s have not yet been identified, last updated November, 2010 (wq-strm7-33c)

Links

Contacts

For questions about the stormwater programs and impaired watersL Josh Stock, 651-757-2235.