Difference between revisions of "Guidance for meeting temperature TMDL MS4 permit requirements"
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| − | This page provides guidance for <span title="A municipal separate storm sewer system (MS4) is a means of transportation, individually or in a system, (e.g. roads with drainage systems, municipal streets, catch basins, curbs, gutters, ditches, man-made channels, storm drains, etc.) that are: owned or operated by a public entity (e.g. cities, townships, counties, military bases, hospitals, prison complexes, highway departments, universities, etc.) with jurisdiction over disposal of sewage, industrial wastes, stormwater, or other wastes. This includes special districts under State law (sewer, flood control, or drainage districts, etc.), an authorized Indian tribal organization, or a designated and approved management agency under section 208 of the Clean Water Act; designed or used for collecting or transporting stormwater; not a combined sewer; and not part of a publicly owned treatment works."> '''MS4'''</span> (Municipal Separate Storm Sewer System) permittees who have permit requirements for | + | This page provides guidance for <span title="A municipal separate storm sewer system (MS4) is a means of transportation, individually or in a system, (e.g. roads with drainage systems, municipal streets, catch basins, curbs, gutters, ditches, man-made channels, storm drains, etc.) that are: owned or operated by a public entity (e.g. cities, townships, counties, military bases, hospitals, prison complexes, highway departments, universities, etc.) with jurisdiction over disposal of sewage, industrial wastes, stormwater, or other wastes. This includes special districts under State law (sewer, flood control, or drainage districts, etc.), an authorized Indian tribal organization, or a designated and approved management agency under section 208 of the Clean Water Act; designed or used for collecting or transporting stormwater; not a combined sewer; and not part of a publicly owned treatment works."> '''MS4'''</span> (Municipal Separate Storm Sewer System) permittees who have permit requirements for temperature <span title="the amount of a pollutant from both point and nonpoint sources that a waterbody can receive and still meet water quality standards"> [https://stormwater.pca.state.mn.us/index.php?title=Total_Maximum_Daily_Loads_(TMDLs) '''total maximum daily load''']</span> <span title="the portion of a receiving water's assimilative capacity that is allocated to one of its existing or future point sources of pollution"> '''wasteload allocations'''</span>. |
==Total Maximum Daily Loads (TMDLs)== | ==Total Maximum Daily Loads (TMDLs)== | ||
Revision as of 21:36, 9 November 2020
This page provides guidance for MS4 (Municipal Separate Storm Sewer System) permittees who have permit requirements for temperature total maximum daily load wasteload allocations.
Contents
Total Maximum Daily Loads (TMDLs)
Currently there are two approved total maximum daily load (TMDLs) for Brown’s Creek and Miller Creek that include MS4 (Municipal Separate Storm Sewer System) wasteload allocations (WLAs) for thermal loading. Brown’s Creek is impaired for aquatic life due to a lack of cold water fish assemblage. Miller Creek is impaired for aquatic life due to a lack of cold water fish assemblage and elevated water temperature.
Permit requirement
Section 22.7 of the MS4 permit contains the following requirement:
If the permittee has an applicable WLA for temperature that includes a reduction greater than zero percent (i.e., City of Duluth, City of Hermantown, City of Rice Lake, City of Stillwater, MnDOT Outstate, St. Louis County, University of Minnesota - Duluth, and Lake Superior College), the permittee must maintain a written plan that identifies specific activities the permittee will implement to reduce thermal loading during the permit term. The written plan may include, but is not limited to:
a. implementation of infiltration BMPs such as bioinfiltration practices;
b. disconnection and/or reduction of impervious surfaces;
c. retrofitting existing structural stormwater BMPs; or
d. improvement of riparian vegetation.
MS4s with applicable temperature WLAs
Link to this table
| TMDL Project | MS4 with a WLA for temperature |
|---|---|
| Browns Creek TMDL | Stillwater City |
| Miller Creek TMDL | Duluth City |
| Hermantown City | |
| Rice Lake City | |
| MnDOT Outstate | |
| St. Louis County | |
| University of Minnesota-Duluth | |
| Lake Superior College |
Guidance for meeting temperature TMDL permit requirements
The TMDL reports for Browns Creek and Miller Creek provide information on potential BMPs/activities that may be included in the written plan to reduce heat and meet the requirements of Section 22.7.
Brown’s Creek TMDL
- Brown’s Creek Impaired Biota TMDL
- Brown’s Creek TMDL Implementation Plan
- Brown’s Creek Watershed District 2017-2026 Watershed Management Plan