Flutterby™! : Filtering streamwater

Northwest Treaty Tribes: Nisqually Tribe’s system shows promise in fighting threat to salmon, helping to remove tire dust, and the associated 6PPD, from stream water:

The tribe teamed up with Long Live the Kings, Herrera Environmental Consultants and Cedar Grove, among others, to place a newly developed biofiltration unit at Ohop Creek. The creek is a tributary to the Nisqually River and home to a large salmon habitat recovery project. It’s also near Highway 7, a busy road that sees vehicles deposit 12 pounds of tire dust on its surface every year—tire dust that rainstorms can wash into nearby habitat.

Developed by Cedar Grove, the biofiltration device applies the concepts of in-ground biofiltration to a mobile unit. Filtering stormwater through two layers—compost and a layer that removes phosphorus—the unit captured stormwater from three storms last year, with its results at leaching out harmful chemicals from that stormwater closely studied.