This page provides guidance for completing the Municipal Separate Storm Sewer System (MS4) Permit TMDL Application Form. Completing and submitting this form is a requirement for permittees who have Total Maximum Daily Load (TMDL) Wasteload Allocations (WLAs) for total phosphorus (TP), total suspended solids (TSS), oxygen demand, or nitrate.

Description of the form

Each MS4 Permit TMDL Application Form is a custom created workbook for each permittee with United States Environmental Protection Agency (USEPA) approved Total Maximum Daily Load (TMDL) wasteload allocations (WLAs). The workbook consists of eight tabs. Three tabs are informational - for the permittee to reference in order to complete the MS4 Part 2 Permit Application, or to reference while completing the other five tabs in this workbook.

Information tab

General instructions on how to complete the form, and reference links.

Screenshot of Municipality X Applicable WLAs for Bacteria, Temperature or Chloride
Image of Applicable Bacteria, Temperature or Chloride WLAs for Municipality X. Click on Image to enlarge

Bacteria Chloride Temp tab

Informational tab- lists any applicable WLAs for bacteria, chloride or temperature TMDL projects (USEPA approved, more than a zero % reduction). Use the information in this tab to answer questions 141, 146 and 151 in the MS4 Part 2 Permit Application. If there is not a project listed for any certain pollutant, you would check the 'No' box for the corresponding question(s) in the MS4 Part 2 Permit Application.

Applicable WLAs determination tab

This tab includes two separate lists. The list in Column A contains any applicable WLAs (USEPA approved, more than a zero % reduction) for oxygen demand, nitrate, TSS, or TP TMDL projects. They are listed by TMDL project name-waterbody-(waterbody id)-pollutant. Column F lists the corresponding applicable numeric WLAs for those projects. If Columns A and F do not show any projects, you do not have any applicable WLAs, and you do not need to complete the TMDL Application. The list of permittees who have no applicable WLAs are located here. Otherwise, the applicant needs to make a determination if they are meeting each WLA or not and type 'Yes' or 'No' in Column B. Once the determination is made, there is a macro that needs to run, and this will autopopulate the rest of the workbook.


In order to complete that determination, the following will be needed:

  • An inventory of structural stormwater BMPs and non-structural BMPs (e.g. establish ordinance, education and outreach, illicit discharge elimination, etc.) within the watershed boundary to the impaired water and that are being applied toward meeting the WLA(s). To determine watershed boundaries see the specific TMDL report or retrieve shapefiles from the MPCA.
  • An estimate of annual cumulative pollutant load reductions (pounds or percent) for implemented BMPs.
  • An estimate of pollutant loading rates (lb/ac/yr) to the impaired water.
Screenshot of Compliance Schedule tab
Screenshot of example Compliance Schedule Tab, before filling in schedule.

Compliance schedule tab

This tab needs to be completed for each WLA that is not being met. Permittees will fill in the target year that each of the applicable WLA(s) will be achieved for each TMDL- waterbody- pollutant project listed in column A. If there is an applicable WLA for total suspended solids (TSS) or total phosphorus (TP), a cumulative estimate of TSS and TP load reductions to be achieved during the permit term and the method used to determine the estimate should be entered in Columns D and E.

Compliance schedule BMPs tab

Screenshot of Compliance Schedule BMPs tab
Screenshot of example Compliance Schedule BMPs Tab, before filling in BMPs.

This tab will be filled in with proposed best management practices (BMPs) or progress toward implementation of BMPs to be achieved during the permit term, anticipated number of practices (if the permittee is planning to install more than one of any type of BMP), and the year each BMP is expected to be implemented ("Implementation Year(s)" column). Put an "X" in the boxes for the TMDL that corresponds with each BMP.

Reductions for WLAs met tab

Screenshot of Reductions for WLAs met tab
Screenshot of example Reduction for WLAS Met Tab, before filling in reductions.

This tab requires the permittee to submit required information for each applicable oxygen demand, nitrate, TSS and/or TP WLA they are claiming to meet. This substantiation needs to be completed using an MPCA-approved method. This should either demonstrate the cumulative estimated reductions from BMPs that serve to meet the MS4 WLA reductions included in the TMDL report OR demonstrates the MS4's existing load meets the WLA.

BMPs for WLAs met tab

Screenshot of WLAs met BMPs tab
Screenshot of example WLAs met BMPs Tab, before filling in BMPs.

This tab requires the permittee to submit required information for each applicable oxygen demand, nitrate, TSS and/or TP WLA they are claiming to meet with a list of all stormwater BMPs implemented to achieve the applicable WLA. For structural BMPs, it is required to include the BMP type, year implemented, location in geographic coordinates (x coordinate and y coordinate), and owner.

Master list tab

This table is for reference only and shows ALL waste load allocations assigned to an MS4 and all flow zones, whether they need to be reported on in the TMDL application or not. This is a filterable list, and can be changed to show other permittees, projects, etc.


1. For categorical WLAs – Are MS4 communities to report on BMPs in just their community, or do they also present data from other communities in the watershed to demonstrate compliance or progress towards the categorical WLA?

  • Please see guidance at Guidance for categorical TMDLs. If the communities have agreed to work together, then data from other communities would be presented. If not, determine the permittee’s portion of the categorical WLA and present data towards that.

2. For categorical WLAs – Can private BMPs constructed in the watershed that have an overall pollutant reduction be included?

  • Refer to the specific TMDL’s WLA methodology, in case certain areas have been excluded from the WLA; but generally, if it discharges to the conveyance system within the watershed, it should be creditable.

Please submit questions to Anna Bosch at the MPCA.


Related pages and useful links