Drainage and Stormwater

BMPs and Stormwater management

See the Stormwater Management Plan for information on procedures, format and guidelines.

For more information, refer to the Stormwater and Watershed Design Considerations for Development.

Lenexa’s Stream Setback Ordinance is based on the Lenexa Stream Inventory (2001), an environmental evaluation of the streams and adjacent riparian corridors. The ordinance defines streams by environmental rating and stream order to determine setback distances. The Western Lenexa Stream Type Map, incorporated in the ordinance as Exhibit A, indicates stream type and order information to be used in the determination of stream setback requirements. An example application of the Stream Setback Ordinance is depicted in the Stream Corridor Zones graphic. This particular application depicts a publicly owned corridor with trails. The corridor may remain in private ownership, but development and use restrictions still apply.

Flood plain and FEMA

The Federal Emergency Management Agency (FEMA) has assigned risk zones to more than 19,000 communities in the United States. These risk zones or Special Flood Hazard Areas are more commonly known as flood plains. The City of Lenexa, as required by FEMA, assists in regulating these flood plains.

Minimum Low Opening and Minimum Floor Elevation

In assisting FEMA with regulation of the Special Flood Hazard Areas, the City of Lenexa has adopted a Flood Prevention ordinance. Two components of this ordinance are minimum low openings (MLOs) and minimum floor elevations (MFEs). A MLO is the elevation of the lowest opening into a structure. A MFE is the elevation of the lowest floor (including basement) within a structure. In order to minimize flooding, the city’s ordinance requires certain freeboard (or distance above) requirements for either MLOs or MFEs in relation to both natural and manmade water and stormwater features.

Rain to Recreation program

Lenexa’s Rain to Recreation program is nationally recognized for its approach to stormwater management, natural resource conservation and restoration, and citizen engagement in natural resource management. The program’s mission is to reduce flooding, protect water quality and natural habitat and provide educational and recreational opportunities.