Line 1: Line 1:
 
[[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 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:
+
==Introduction==
 +
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.  
 +
 
 +
==Requirements==
 +
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 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 requires the use of green infrastructure.
Line 10: Line 14:
 
:*All documentation described [https://stormwater.pca.state.mn.us/index.php?title=Documentation_requirements_and_documents_to_retain_under_the_MS4_permit here].  
 
:*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:
+
==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 17:21, 4 January 2018

Infiltration basin protected by silt fence during construction

Introduction

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.

Requirements

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