In all cases the SWPPP needs to be “completed” prior to submitting the permit coverage application.
The SWPPP generally does not need to be “submitted” to the MPCA at the time of permit application. For certain projects or common plans of development or sale disturbing 50 acres or more and the site has a discharge point that flows to a special or impaired water within a mile of the site, application must be submitted at least 30 days before the start of construction activity.
Failure to prepare an accurate and complete SWPPP prior to submitting the application invalidates the application and the stormwater discharges associated with construction activity will not be authorized by this permit.
In all cases the SWPPP must be retained on site (see the permit for details) during construction and the owners must retain the SWPPP on file for three years after construction has been completed.
If the following three things are true, then the SWPPP must be submitted to the MPCA for review at least 30 days prior to the start of construction activity:
If any or all of the three items above are not true, then the SWPPP does not have to be approved prior to submittal of the permit coverage application.
It means the shortest straight line distance measurement between the point of stormwater discharge from a project construction site to the nearest edge of the water body the stormwater will flow to. This measurement does not follow the meander flow path.
A SWPPP does not need to be submitted for review for sites 50 acres or more if stormwater from the site does not flow to the special or impaired water even though it may be located within a mile of the site. This may be the case if the existing topography is such that stormwater from the site will not ultimately flow into the special or impaired water because the site is not located in the same watershed as the special or impaired water. However, the SWPPP must still be submitted if stormwater from the site will ultimately reach the waterbody even if the stormwater does not flow directly into the impaired or special water located within a mile of the site.
This guidance is offered to assist the regulated parties but does not replace nor does following this guidance excuse noncompliance with the permit.
Sites located near impaired waters listed under section 303(d) of the federal Clean Water Act (see the MPCA’s web site) where the identified pollutant(s) or stressor(s) are phosphorus (nutrient eutrophication biological indicators), turbidity, dissolved oxygen, or biotic impairment (fish bioassessment, aquatic plant bioassessment and aquatic macroinvertebrate bioassessment are required to comply with the NPDES/SDS Construction Stormwater permit requirements.
The MPCA website has a Special and Impaired Water Search tool that can be found here. The tool provides a visual way to locate waters within 1 mile of the site and choosing the topographic version can help determine if stormwater will flow to the waterbody. A measuring tool is also available to determine the distance to the water body. The actual 303(d) list of impaired waters can also be found at MPCA’s website. The regulated party is required to make the determination whether stormwater will flow to the water body and that the SWPPP requires review prior to obtaining permit coverage. Additional impaired waters are likely to be added to the list in future years and others might be deleted from the list once the water is no longer impaired. The list is updated every 2 years. If uncertain about the status of particular waterbody, the regulated party may contact the MPCA Stormwater Hotline at 651-757-2119 or 800-657-3804.
The SWPPP may be submitted in either paper or digital formats. Digital formats are preferred to conserve on the amount of paper use and for filing efficiency. Smaller size SWPPPs (less than 24MB) can be e-mailed to the MPCA at CSW.email@example.com. Extremely large SWPPPs such as those with numerous photos, maps, etc. can be submitted to the MPCA on a CD or other digital storage devise. Hardcopies of SWPPPs can also be submitted by U.S. Mail or hand-delivered to the MPCA. If you have questions about submitting your SWPPP call MPCA Stormwater Hotline at 651-757-2119 or 800-657-3804.
The applicant must allow up to 30 days for staff to review the SWPPP. Once MPCA staff have reviewed and approved the SWPPP, the permit can be issued. The applicant receives notice once permit coverage has been granted.