Successful programs lead to painless permitting.

Whether you’re new to the MS4 Permit or have an ongoing established program, successful implementation and management of an MS4 program requires a clear understanding of permit requirements and solid teamwork.

A Municipal Separate Storm Sewer System (MS4) is a conveyance or system of conveyances (i.e., municipal streets, catch basins, curbs, gutters, ditches, channels, etc.) that is designed to collect stormwater and is owned and operated by a public entity. Stormwater from an MS4 is regulated under the National Pollutant Discharge Elimination System (NPDES) MS4 permit to reduce pollution from conveyance systems. Communities that own and operate a MS4 are required to minimize pollutants that enter their systems through a Stormwater Pollution Prevention Plan (SWPPP). Each SWPPP includes six minimum control measures that address the following areas: public education and outreach, public participation and involvement, illicit discharge detection and elimination, construction site runoff control, post-construction site runoff control, and good housekeeping.

Is your MS4 program audit-proof? Let us help you prepare for the next permit cycle and any potential upcoming audits. Our team of environmental compliance specialists can help you understand and achieve MS4 compliance to meet regulations and maintain the integrity of your stormwater conveyance system.

Every MS4 faces unique stormwater challenges, but each program contains the same six minimum control measures. Our team of specialists are trained to assist cities, counties, watershed districts, colleges, and townships with MS4 compliance assistance for a range of system sizes and needs. We balance your needs and abilities with regulations to provide consistent, practical means to manage processes, inspections, recordkeeping, training, and more.

Our approach to MS4 compliance has been thoroughly vetted during MPCA audits. We can help you meet MS4 permit requirements, avoid unnecessary fines, and most importantly, prevent harmful pollutants from entering your stormwater conveyance system.

Important MS4 Deadlines

Annual Deadlines

  • June 30: Annual Report is due to the MPCA
  • December 31:
    • Hold your MS4 Annual meeting by this date
    • Complete all structural stormwater BMP inspections by this date
    • Complete annual MS4 training for all permanent and seasonal field staff by this date
    • Complete annual program analysis and documentation by this date

Ongoing Deadlines

  • Quarterly: Inspect all stockpiles and facilities once per quarter
  • July 31, 2018: Complete all visual pond and outfall inspections by this date

To learn more about how WSB can help your organization please contact us:

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