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Stormwater Permit
Public Participation
Total Maximum Daily Load
Public Education
Illicit Discharge Elimination Program
Post Construction Stormwater Management
Construction Stormwater Controls
Pollution Prevention and Good Housekeeping

Watershed Stormwater Permit

The City of Ann Arbor is one of several Huron River communities partnering to develop a watershed-based stormwater permit. Working collaboratively provides all watershed permit partners greater flexibility in developing strategies and implementing the permit requirements. The collaborative approach is desiged to accomplish stormwater quality improvements watershed-wide, and provides an added benefit of cost sharing for some stormwater controls.

Ann Arbor's Stormwater Permit

Federal and state regulations require urban communities to address both the amount of runoff and the pollution carried by that runoff that is deposited, untreated, into surface waters. Specifically, stormwater discharges in Ann Arbor are regulated under the National Pollution Discharge Elimination System (NPDES) Municipal Separate Storm Sewer System (MS4) permit. Under this permit, the city must comply with several requirements, which, if implemented, should result in a significant reduction in pollutants discharged to receiving waters. Required components of the permit include:

Watershed Management Plan

The Middle Huron River Watershed Management Plan was developed in 1994, and was updated in 2000 and again in 2008. The plan lays out strategies to protect sensitive natural areas in the Middle Huron Watershed, mitigate impacts of existing point and non-point source pollution, and restore degraded areas. 

Public Participation Plan (PPP)

Municipalities must develop a procedure for giving the public an opportunity to participate in both the development and implementation of a stormwater program. The Public Participation Plan for the Middle Huron River Subwatershed (pdf) was developed and submitted to the MDNRE in August 2009.

Storm Water Management Program (SWMP)

The Storm Water Management Program (SWMP) details the specific actions watershed partners will implement to meet the permit requirements. The SWMP has six main pieces.

1. Total Maximum Daily Load (TMDL)
Municipalities must identify and prioritize actions to reduce pollutants in stormwater discharges to make progress toward meeting water quality standards. A TMDL plan has been developed for the watershed permit partners and can be found here (pdf).

2. Public Education Program (PEP)
Municipalities must develop a program to promote, publicize, and facilitate educational materials and activities on stormwater and pollution prevention. This plan must be developed and implemented in partnership with other permitted communities in the watershed.

3. Illicit Discharge Elimination Program (IDEP)
Municipalities must develop a plan with mechanisms designed to locate and eliminate discharges into storm sewer from sources other than stormwater.

4. Post Construction Stormwater Management
Municipalities must have a program requiring new and redevelopment projects to implement on site controls that will reduce pollutant loads in stormwater runoff.

5. Construction Stormwater Controls
Municipalities must have a regulatory mechanism in place for erosion and sediment control, as well as best management practices (BMPs) for preventing or reducing other pollutants associated with construction activity.

6. Pollution Prevention and Good Housekeeping Practices for Municipal Operations
Municipalities must have an operation and maintenance program to prevent or reduce pollutant runoff from municipal operations.

Updated January 2012


Middle Huron Watershed


The  Middle Huron Watershed covers nearly 300 square miles. It includes 16 townships, 3 cities, 3 villages, and 2 counties.

Watershed Stormwater Permit Partners include:

City of Ann Arbor

City of Ypsilanti

Eastern Michigan University

Charter Township of Pittsfield

Village of Dexter

Charter Township of Ypsilanti

Washtenaw County Road Commission

Washtenaw County Water Resources Commissioner



The following documents were submitted to the MDNRE under the current watershed stormwater permit.

Public Participation Plan (pdf, developed by HRWC)

Storm Water Management Program (SWMP) (pdf)

TMDL Implementation Plans (developed by HRWC)
Mallets Creek (pdf)
Swift Run (pdf)
Ford and Belleville
Lakes (pdf)

Huron River (Argo to Geddes) (pdf)

Public Education Program Template & Activity Table (pdf, developed by HRWC)



Jennifer Lawson
Water Quality Manager
(734) 794-6430, Ext 43735

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