Difference between revisions of "MCM 5 Post-Construction Stormwater Management"
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[[File:InfiltrationBasinDuringConst.JPG|thumbnail|right|Infiltration basin protected by silt fence during construction]] | [[File:InfiltrationBasinDuringConst.JPG|thumbnail|right|Infiltration basin protected by silt fence during construction]] | ||
| − | Paved surfaces exacerbate the negative impacts | + | Paved surfaces exacerbate the negative impacts to stormwater, including a increasing the stormwater discharge volume and pollutants in stormwater. Managing stormwater onsite post-construction is the more effective way to mitigate these impacts. Minimum Control Measure (MCM) 5 of the [https://stormwater.pca.state.mn.us/index.phptitle=MS4_PART_III.STORMWATER_POLLUTION_PREVENTION_PROGRAM_(SWPPP) municipal seperate storm sewer system (MS4) General Permit] requires permittees to have and enforce a post-construction stormwater management program that prevents or reduces stormwater pollution in new- and re- development projects. The post-construction stormwater management program should include: |
| + | :*A regulatory mechanism that requires proposers of construction activity to submit site plans with post-construction stormwater management best management practices (BMPs) | ||
| + | :*A regulatory mechanism that requires the use of green infrastructure. | ||
| + | :*A regulatory mechanism that specifies that there will be no net increase in stormwater volume, total suspended solids (TSS), and total phosphorus (TP) from new development projects; and a net decrease in volume, TSS, and TP for redevelopment projects. See [https://www.pca.state.mn.us/sites/default/files/wq-strm4-59e.pdf MPCA this fact sheet] for the different methodologies to employ to meet this requirement. | ||
| + | :*A regulatory mechanism that prohibits infiltration in certain situations, and restricts it in others, as described [https://stormwater.pca.state.mn.us/index.php?title=When_infiltration_is_not_authorized_under_a_stormwater_permit here]. | ||
| + | :*Mitigation provisions if TSS and TP cannot be managed onsite. | ||
| + | :*A long term maintenance agreement for private structural stormwater BMPs. We have three templates available for your use, [https://stormwater.pca.state.mn.us/index.php?title=Example_Maintenance_Agreement_1 a basic maintenance agreement], [https://stormwater.pca.state.mn.us/index.php?title=Example_Maintenance_Agreement_1 a maintenance agreement for rain gardens], and [https://stormwater.pca.state.mn.us/index.php?title=Example_Maintenance_Agreement_3 a maintenance agreement for stormwater quality treatment facilities]. | ||
| + | :*Site plan review procedures to ensure the post-construction stormwater management is in accordance with the regulatory mechanism. See [https://stormwater.pca.state.mn.us/index.php?title=MS4_Staff_Site_Plan_Review_Guidance] for more information on what to look for during the site plan review. | ||
| + | :*All documentation described [https://stormwater.pca.state.mn.us/index.php?title=Documentation_requirements_and_documents_to_retain_under_the_MS4_permit here]. | ||
| + | Additional resources: | ||
*[https://www.epa.gov/npdes/national-menu-best-management-practices-bmps-stormwater#post EPA MCM 5 guidance] - EPA's guidance and suggested BMPs for an effective post-construction stormwater management program | *[https://www.epa.gov/npdes/national-menu-best-management-practices-bmps-stormwater#post EPA MCM 5 guidance] - EPA's guidance and suggested BMPs for an effective post-construction stormwater management program | ||
*[https://www.pca.state.mn.us/sites/default/files/p-gen3-07.pdf MPCA Minimal Impact Design Standards guidance] - MPCA fact sheet on Minimal Impact Design Standards (MIDS) and how communities can adopt the MIDS requirements | *[https://www.pca.state.mn.us/sites/default/files/p-gen3-07.pdf MPCA Minimal Impact Design Standards guidance] - MPCA fact sheet on Minimal Impact Design Standards (MIDS) and how communities can adopt the MIDS requirements | ||
*[https://www.pca.state.mn.us/sites/default/files/wq-strm4-59e.pdf MPCA MCM 5 Technical Support guidance] - MPCA guide to how to comply with MCM 5 post-construction stormwater management requirements | *[https://www.pca.state.mn.us/sites/default/files/wq-strm4-59e.pdf MPCA MCM 5 Technical Support guidance] - MPCA guide to how to comply with MCM 5 post-construction stormwater management requirements | ||
Revision as of 22:27, 6 November 2017
Paved surfaces exacerbate the negative impacts to stormwater, including a increasing the stormwater discharge volume and pollutants in stormwater. Managing stormwater onsite post-construction is the more effective way to mitigate these impacts. Minimum Control Measure (MCM) 5 of the municipal seperate storm sewer system (MS4) General Permit requires permittees to have and enforce a post-construction stormwater management program that prevents or reduces stormwater pollution in new- and re- development projects. The post-construction stormwater management program should include:
- A regulatory mechanism that requires proposers of construction activity to submit site plans with post-construction stormwater management best management practices (BMPs)
- A regulatory mechanism that requires the use of green infrastructure.
- A regulatory mechanism that specifies that there will be no net increase in stormwater volume, total suspended solids (TSS), and total phosphorus (TP) from new development projects; and a net decrease in volume, TSS, and TP for redevelopment projects. See MPCA this fact sheet for the different methodologies to employ to meet this requirement.
- A regulatory mechanism that prohibits infiltration in certain situations, and restricts it in others, as described here.
- Mitigation provisions if TSS and TP cannot be managed onsite.
- A long term maintenance agreement for private structural stormwater BMPs. We have three templates available for your use, a basic maintenance agreement, a maintenance agreement for rain gardens, and a maintenance agreement for stormwater quality treatment facilities.
- Site plan review procedures to ensure the post-construction stormwater management is in accordance with the regulatory mechanism. See [1] for more information on what to look for during the site plan review.
- All documentation described here.
Additional resources:
- EPA MCM 5 guidance - EPA's guidance and suggested BMPs for an effective post-construction stormwater management program
- MPCA Minimal Impact Design Standards guidance - MPCA fact sheet on Minimal Impact Design Standards (MIDS) and how communities can adopt the MIDS requirements
- MPCA MCM 5 Technical Support guidance - MPCA guide to how to comply with MCM 5 post-construction stormwater management requirements