Construction and Performance of Bioretention Cells

Bioretention cell are gaining popularity as a stormwater best management practice (BMP). This can be largely attributed to the fact that they present a broad range of potential benefits such as decreased runoff, thermal attenuation, aesthetics and improved water quality through various physical, chemical and biological processes. Ten prototype cells were constructed in Oklahoma as part of an ongoing demonstration project. The cells ranged in size from 19 m³ to 435 m³, and the filter media incorporated fly ash to enhance phosphorus and heavy metal retention. Eight of the cells were installed in Grove, Oklahoma by a contractor, while the other two were constructed in Stillwater by the authors. This paper discusses engineering considerations, general design procedures, cell specifications, construction costs and issues that arose during construction.