Biofiltration Media – Phosphate release or capture, plant growth, chloride impacts, and more!

Thursday April 13, 2:00 - 3:00 PM


Biofilters are rain gardens with underdrains that treat stormwater runoff from urban landscapes, especially where infiltration into shallow groundwater is infeasible or a concern. The biofilter media (e.g., sand, compost, peat, biochar), however, can release phosphate or limit plant growth, so stormwater professionals struggle to choose which media to use in biofilters. A four-year outdoor research study evaluated thirteen different mixes of eight different media components to determine benefits and consequences of using common and new innovative media components in biofiltration media. This presentation will share the final performance results including phosphate release or capture, plant growth, filtration rate, impacts from road salt addition on phosphate release, and simple tests and metrics that could be used to determine which components have potential to release phosphate. The final recommendations from this project are intended to guide stormwater practitioners towards better designed biofiltration practices that capture phosphorus and support healthy vegetation.

Event Speaker
photo of andy

Andy Erickson, Research Manager - St. Anthony Falls Laboratory, University of Minnesota; Vice Chair - ASTM Committee E64 on Stormwater Control Measures; Chair - University of Minnesota Water Council

Andy Erickson, PhD, PE, is a Research Manager at St. Anthony Falls Laboratory and the University of Minnesota and registered professional engineer in Minnesota. Dr. Erickson's research pursues an understanding of water quality in urban and agricultural watersheds, assessment and maintenance of stormwater treatment practices, and developing new stormwater treatment technologies such as the Iron-Enhanced Sand Filter. Dr. Erickson is lead author for the book "Optimizing Stormwater Treatment Practices: A Handbook of Assessment and Maintenance" and the editor of the University of Minnesota stormwater newsletter, UPDATES to approximately 1900 email subscribers, and leads the Minnesota Stormwater Seminar Series for approximately 170 stormwater practitioners per month. Dr. Erickson has given over 230 presentations, over 30 invited guest lectures, and over 40 one-and two-day professional trainings and workshops. Dr. Erickson is the Vice Chair of the ASTM international E64 Committee on Stormwater Control Measures and a member of the Water Environment Federation Stormwater Institute Advisory Board. Dr. Erickson also serves the University of Minnesota as the Chair of the Water Council, a member of the St. Anthony Falls Lab Executive Committee, a member of the Civil, Environmental, and Geo-Engineering Graduate Faculty, an affiliate member of the Water Resources Science Graduate Program, a member of the Center for Transportation Studies Scholar Program, and a member of the Environment and Energy in Transportation Research Council.