40th and Butler Avenue Drainage Improvements
This project included drainage improvements in the residential/urban area of the Butler neighborhood. The project is for the design of approximately two miles of hybrid ditches primarily along Grand Avenue, Butler Avenue, and Hawthorn Lane that will tie into existing storm water infrastructure. Hybrid ditches are being designed for sustainability and water quality improvements, which will allow stormwater runoff to percolate into the soil to replenish ground water.
The hybrid ditch consists of a perforated HDPE pipe in a stone envelope to allow storage of runoff in the void space and a positive outlet for water reaching the perforated pipe. Since a majority of the runoff will infiltrate through the grassed swales, water quality will increase by reducing the amount of sediment transported in the storm flows. The proposed drainage system will also diminish the peak flow rate seen by the existing downstream infrastructure. Additionally, mechanically stabilized stone and/or pervious pavers are being analyzed as potential solutions for the parking areas to allow for the infiltration of stormwater, further reducing the possibility for standing water in the street as well as area flooding.