Frequently Asked Questions

All Single Family Residential Construction and Any Project Disturbing 5,000 square feet or more, within the City of Owatonna are required under the Stormwater Management Ordinance to obtain a Grading / Erosion and Sediment Control (ESC) Permit from the Engineering Department.

Please visit the Construction Stormwater page for further information as well as access to applications and fees.

Low Impact Development or LID is a stormwater management approach and site-design technique that emphasizes water infiltration, values water as a resource and promotes the use of natural systems to treat water runoff. Low impact development is a way to mimic the natural process and to avoid water pollution.

Low impact development approach employs distribution management techniques, called integrated management practices (IMPs). LID IMPs are used to satisfy storage and infiltration of stormwater. 

Management practices that are suited to low impact development include:

• Bioretention facilities
• Disconnecting roof drains
• Infiltration swales and trenches
• Rain Barrels
• Rain Gardens
• Vegetative buffers and strips

The City of Owatonna was awarded a $500,000 Low Impact Development (LID) grant in June 2008 by the Minnesota Pollution Control Agency (MPCA). The grant will assist the city with development of stormwater management infrastructure designed to reduce the volume and rate of runoff and ultimately improve water quality.

The grant funds will be used to complete several LID projects in various locations throughout the city. The projects are designed to address flooding issues in the city and promote LID practices that will result in fewer problems in the future. The city has outlined the following objectives to implement LID practices:

• Education for City Council and Staff
• Mosher Rainwater Garden
• Porous Pavement Alleys
• Project Signage and Reports
• Rose Street Parking Lot Rainwater Garden
• Zoning Code Revisions

Lot grading is an extremely important aspect of conveying from private property to public infrastructure without causing issues on neighboring properties and helps to ensure stormwater management objectives are met. The primary purpose of lot grading is to shape the land to efficiently and effectively direct stormwater away from homes while minimizing impacts to surrounding properties. 

Grading plans are blueprints to carry this process out and it defines how the lot will convey stormwater drainage to designated routes. Based on minimum design standards and best industry practices, they specify design elevations, surface gradients, lot/structure types, swale locations, establishes the grading relationship between adjacent properties. Grading plan review and approval is an effective basis for control of drainage.

To provide a level of protection and assurance to new homeowners and the adjacent landowners, the City of Owatonna requires a Certification of Critical Elevations as part of the permitting process. This ensures the lowest opening to the home has adequate freeboard to any nearby ponding areas, high water levels, emergency overflow routes, and overall lot grading is sufficient when the home is complete. This certification replaces an outdated policy related to foundation height that serves little to no benefit in protecting homes. 

After the contractor achieves certification, property owners are then responsible to maintain these drainage patterns and leave intentionally constructed “common property” swales, concentrated drainage routes, and overflow paths unobstructed and free flowing. This includes properly placing fences, utility sheds, and other landscaping items outside of these designated areas. Even simple landscaping projects may have impact to overall drainage. 

Residential Infill is the practice of constructing and integrating new buildings into existing neighborhoods. Part of the construction process is re-grading the project area to comply with building codes, drainage laws, and ordinance requirements. Infill developments typically do not have a subdivision lot grading plan, and one must be submitted as part of the building permit application. Many older neighborhoods have little to no mass grading. Final grading of each lot is imperative. 

Consulting with adjacent property owners is a critical step when considering any grade changes. In most cases, grading improvements can be made in conjunction with grading for the infill development and avoid future property damage or drainage issues. This may also fix any existing drainage issues, neglected grading, and encourage maintaining common property swales.