What is it?
Sorbtive MediaTM is an oxide-based, high surface area reactive engineered media that absorbs and retains large amounts of dissolved phosphorus. It does not desorb (leach) pollutants and has a low total phosphorus effluent concentration (< 0.1 mg/L). Sorbtive MediaTM controls phosphorus by two mechanisms:
- Physical filtration is the removal of particulate-bound phosphorus and sediment, and
- Sorption is the physio-chemical removal of dissolved phosphorus (the biologically available portion)..
How is it being used?
Imbrium's Sorbtive MediaTM webpage provides links to technical specificationss and design help, along with highlights of multiple projects where the product has been used for phosphorus removal.
At the Sturgeon Meadows Stormwater Management Facility in Leamington, Ontario, Sorbtive MediaTM was applied as a retrofit component to enhance pollutant removal withing an existing dry pond as part of a treatment train. A 30 cm layer was applied within retrofitted trenches in combination with washed stone and rip rap rock to manage the expected treatment flow.
The Rumble Pond Retrofit project in Richmond Hill, Ontario used Sorbtive MediaTM in combination with permeable interlocking pavers to enhance overall capacity of the pervious pavers.
A partnership between Credit Valley Conservation and the University of Guelph completed a project at the IMAX Corporation headquarters in which Sorbtive MediaTM was used downstream of a bioretention cell to provide tertiary nutrient treatment.
A project at Mayville Park in Upstate New York used six retrofit filtration cells surrounding draining inlets near a community centre, which previously had no stormwater treatment on-site.  In addition to these projects included on their website, Sorbtive MediaTM was installed at the Colony Trail retrofit in East Gwillimbury. The Imbrium Sorbtive MediaTM chamber removed an average of 66 % of dissolved phosphate from the site. 
A pilot study was undertaken by researchers at Fleming College in Ontario, Canada to assess the phosphorus removal performance of bioretention soil mix amended with Sorbtive Media. Five bioretention cells were constructed and filled with a soil mix comprised of sand, peat moss, and various percentages of Sorbtive MediaTM. Batches of artificial stormwater containing differing concentrations of phosphorus were used to simulate storm events on the bioretention cells. Through analysis of the influent and effluent concentrations, it was determined that the amended bioretention cells demonstrated substantial improvement in phosphorus removal. Each of the amended cells maintained removal efficiency of up to 99 % and at least 84 % for the duration of the study, even when blended into the soil mix at only 3 - 5 % volume basis.
- Imbrium Stormwater Treatment Solutions. Sorbtive Media. http://www.imbriumsystems.com/stormwater-treatment-solutions/sorbtive-media. Accessed October 6, 2017
- Imbrium Systems. 2017. Sorptive Media. https://www.imbriumsystems.com/stormwater-treatment-solutions/sorbtive-media
- Lake Simcoe Region Conservation Authority (LSRCA). Showcasing Water Innovation: Stormwater Performance Monitoring Report. 2013. http://www.lsrca.on.ca/Shared%20Documents/reports/swi_monitoring_2013.pdf. Accessed October 6, 2017.
- Balch G. Broadbent H, Wootton B, Collins S. Phosphorus Removal Performance of Bioretention Soil Mix Amended with Imbrium Systems Sorbtive Media. 2013. Centre for Alternative Wastewater Treatment, in association with Fleming College. http://www.imbriumsystems.com/Portals/0/documents/sm/technical_docs/Fleming%20College%20CAWT%20Report%20on%20Sorbtive%20Media%20Performance.pdf