
Equinox “Industrial Strength” Green Stormwater Infrastructure (GSI) demonstration site improves water quality in the Duwamish Valley

Sampling water that’s been filtered through an Oyster Shell Cistern (above) and a Grattix box below. Photo Credit: Cari Simson / ECOSS.
Right now, we all need to be sharing good news, especially related to our local water quality. ECOSS and Equinox Studios are proud to announce that after only six months since installation, Phase 1 of the Equinox “Industrial Strength” Green Stormwater Infrastructure (GSI) Demonstration site is actively improving water quality flowing off private property. The Grattix systems (rain gardens in boxes) installed on Equinox’s “Living Room” and “Factory” buildings in late 2019 are already showing success – ECOSS’ water sampling showed these systems reduced zinc in rainwater runoff by 70 to 99% at three downspout locations.
Phase 1 of the Equinox GSI site, built in early 2020, includes three Grattix systems, two oyster shell cisterns and three kinds of permeable pavements. ECOSS, in partnership with Equinox Studios, seeks to provide education and inspiration for businesses and other landowners who want to improve water quality on their properties. For many in dense urban areas, small or compact properties are not suitable for rain gardens, and native soils may be contaminated or have saturated groundwater. Grattix and oyster-shell systems are downspout filters, which allow runoff to flow through plants, soil, rock layers, or used oyster shells to remove copper, zinc and other contaminants. GSI installations also reduce flooding risk as downspout water flows slowly through permeable materials or surfaces rather than accumulate on hard concrete surfaces.
These systems are relatively easy and affordable to install. ECOSS and its partners can provide technical support and resources for design, construction and maintenance. Please reach out to ECOSS (csimson@ecoss.org) if you are interested in learning more.
This phase also completed the Gardens of Gusto, a vegetated wall, or vertical garden, on the exterior of the Factory building at the Equinox complex. The vertical garden will add native plants and hearty vines to the block, irrigated by large cisterns capturing water from the roof.
Learn more about the GSI installations at Equinox
More exciting business-tailored stormwater solutions and education are coming. Here’s a preview of ECOSS’ plans for the Equinox demonstration site.
- Two Grattix-tainers (giant Grattix and planter in one 20′ recycled shipping container box) for the Livingroom will complete all the filtration for the 3000 square foot Livingroom building.
- Two Equibox (Grattix on top of a cistern in one 20′ recycled shipping container box) will capture and treat 7500 square feet of the Factory roof and provide the Gardens of Gusto with irrigation.
- Additional water quality testing in June 2021 to replicate the sampling plan
- Provide businesses in the area with technical and planning support to install Grattixes, Oyster Shell cisterns or permeable paving systems.
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Additional support for the Equinox GSI project was provided by the Boeing Company, King County Flood Control District, and BNSF. Funding for sampling provided by Puget Sound Stewardship and Mitigation fund, a grant making fund created by the Puget Soundkeeper Alliance and administered by the Rose Foundation for Communities and the Environment.
The Port of Seattle provided in-kind contributions of materials for the Oyster Shell Barrels and interpretive signage. Thank you, Aspect Consulting, PureBlue and Equinox Studios for supporting this work through in-kind contributions of time.