Indian Creek Channel Flood Control Improvements
This project was awarded the 2015 KC Metro APWA Environmental Project of the Year and the 2015 ASCE Kansas City Region Project of the Year. The project, which extends along Indian Creek between 153rd Terrace and 151st Street, was jointly funded by the City of Olathe and the Johnson County Stormwater Management Program (SMP).
The flooding issues along this portion of Indian Creek included 8 homes during the 100-year storm, overtopping of 151st Street and 153rd Terrace by nearly 2 feet during the 100-year event and widespread flooding of Lindenwood Drive.
The channel improvements included a unique blending of flood control and environmental enhancement. The existing concrete channel was replaced with a naturalistic, meandering channel with a series of pools and riffles which conveys the 2-year storm. Larger rainfall events safely pass between concrete block retaining walls that define the outer limits of the streamway corridor.
The 153rd Terrace and 151st Street culverts were replaced with precast reinforced concrete box culverts. Weir walls were installed at the upstream end of the outer cells of the new box culverts to mimic the natural channel and minimize siltation and long term maintenance costs.
Immediately north of 151st Street, Indian Creek was in a good condition, so it was important to preserve the natural habitat. In lieu of channel widening and destroying natural habitat, by-pass channels were graded adjacent to the creek to maintain the natural stream bank and riparian vegetation.
In addition to flood control and water quality enhancements, the project included nearly 4,000 feet of sanitary sewer improvements. The existing sewer mains paralleled both sides of the stream and ranged from 15” to 24” diameter vitrified clay pipe. The design solution consolidated all of the sewer mains to one side of the creek with gasketed PVC pipe with diameters ranging from 18” to 27”.