Longevity of biological protection using bioretention

The U.S. Fish and Wildlife Service, in collaboration with Washington State University, is testing how long a bioretention soil mix can be used to reduce pollution from urban stormwater. This study uses the standard bioretention soil mix in experimental columns to evaluate its effectiveness in treating stormwater for 18 months, which simulates 10 water years.    

Study questions

  • How long can the 60:40 standard bioretention soil media prevent acute toxicity from urban stormwater?
  •  What soil depths are necessary to provide sufficient biological protection and water quality treatment?

Study findings

The study will continue until September 2020.

Project tasks and key deliverables

Contract IAA & Scope of Work

  1. Develop Quality Assurance Project Plan
  2. Prepare experimental columns
  3. Conditioning experimental columns
  4. Bioretention performance throughout accelerated aging 
  5. Communication & Outreach
    • Presentations and Factsheet
    • Final report