Cottage Grove’s stormwater pollution prevention program (SWPPP) includes innovative aspects that are reducing the impacts of stormwater on their community and surface waters. One reason the SWPPP is effective is because the City has integrated the program into multiple City departments and uses the expertise of external partners to implement various aspects of the program. This allows all involved to draw on the tools specifically available to them to compel compliance with state and local water quality rules.
The Cottage Grove SWPPP is overseen by the Engineering Division, which is part of the Community Development Department. Also housed in the Community Development Department is the Planning Division. Having both the Engineering and Planning Divisions under one leadership allows staff in each division to work closely early in the planning and approval process for new development and redevelopment projects. Many of the MS4 permit requirements are necessary to be evaluated prior to construction activity starting, such as the locations and types of erosion protection and sediment control or project’s method for permanently managing stormwater discharge volume, total phosphorus, and total suspended solids. Because the Planning Division staff have involved the Engineering Division staff as soon as proposed projects come through City Hall’s doors, MS4 staff can ensure stormwater requirements while they are still in the approval process.
In addition to internal partners, the Engineering Division utilizes external partners in the site plan review process. Cottage Grove is entirely in the South Washington Watershed District (SWWD). SWWD reviews the submitted site plans to determine if the district’s rules are being met. With dozens of projects over an acre being proposed in Cottage Grove over the last few years, city MS4 staff also utilize the expertise of a consultant to conduct the engineering reviews for some project’s permanent stormwater systems. These types of collaborations are highly successful in efficiently managing a successful MS4 program.
To coordinate the various divisions and partners during the site plan review process, Cottage Grove has developed an eight step site plan review process. The process is designed so the city and its partners can raise questions and concerns with the applicants at numerous stages of the approval process. Final building or grading permits are not issued until all portions of the project are in line with with city, state, and watershed district stormwater management rules.
After the building or grading permit is issued, the Engineering Division works with another division in the Community Development Department, the Building Division, and SWWD during the project’s construction phase. SWWD conducts erosion and sediment control site inspections on all private construction projects on behalf of the Engineering Division. These inspections, conducted twice per month, determine compliance with City, Watershed, and MPCA’s construction stormwater and MS4 permit requirements. To emphasize the importance of these inspections, findings, and required corrective actions to the developer/contractor, the City’s building official is copied on all erosion control inspection reports.
If violations are observed onsite by the SWWD inspector, the Engineering Division will follow up on the requested corrective actions. If a project has repeated noncompliance, the Engineering Division staff can request that the Building Division suspend building inspections until the noncompliance is corrected, which means construction must be halted. Needless to say, the threat of stopping building inspections generally compels compliance. However, if the noncompliance isn’t corrected and the City needs to take on the responsibility of remedying the situation, the City can recoup its lost resources by drawing on the developer’s line of credit. Without the close relationship with the Building Division, the Engineering Division wouldn’t be able to leverage the tools available to the Building Division, such as building inspections and line of credit.
Cottage Grove has developed a SWPPP that spans multiple city departments. By doing this, the City’s MS4 staff in the Engineering Division is able to be incorporated in the construction planning during the initial phases and utilize tools available to other divisions to compel compliance with the MS4 permit.