Stormwater runoff is the #1 source of Puget Sound pollution. There are multiple contributing factors and chief among them are the toxicants that are ubiquitous in urban environments, such as metals deposited on roads by vehicles, air pollution deposited on roofs and more. Such toxicants are picked up by the rain on the way to storm drains that flow untreated into our water bodies. And during large storms, the rains can overwhelm sewer systems. Consequently, the polluted stormwater doesn’t reach treatment plants and flow untreated into local water bodies.
Green Stormwater Infrastructure (GSI) is an effective solution to mitigating stormwater pollution. Cisterns lower the volume of water entering stormwater systems during storms and lower the risk of overflowing combined sewer systems. Rain gardens slow the flow of rainwater while naturally filtering toxins. Programs such as the RainWise rebate program have increased access to stormwater solutions for residents throughout Seattle.
ECOSS seeks to broaden the acceptance of GSI in our region by providing technical services for businesses to help reduce their stormwater pollution. The Duwamish River manufacturing and industrial area has many businesses that rely on their location to do their work. During large storms, these businesses are not only dealing with operational costs in the case of flooding problems, but also potentially responsible for pollution that their properties contribute to the Duwamish River.
Green Stormwater Infrastructure (GSI) for industrial businesses can help with both flooding concerns and reduce pollution from contaminants that land on rooftops and wash into storm drains. But most businesses have space limitations and operational needs, and the solutions need to be affordable and scalable. Businesses may not know about the breadth of GSI solutions that are possible on their properties, which is where ECOSS can be of service!

Multicultural contractors apply their knowledge of residential GSI solutions to Grattix box construction. Photo Credit: William Chen / ECOSS.
In 2018, ECOSS partnered with Equinox Studios to develop a first of-its-kind, large-scale GSI demonstration site in an industrial area. Equinox Studios, located in the industrial heart of Georgetown, attracts over 18,000 visitors per year and is ideally situated to promote GSI to local industrial businesses and communities. The site showcases emerging and cost-effective GSI solutions that can be easily adopted by property owners seeking to control polluted runoff. When finished in 2020, the Equinox installation will collect stormwater from 62,000 square feet of roof space and passively filter 1.3 million gallons of water annually. ECOSS Equinox Studios represents an immense potential to reduce toxicants from polluting local waters.

Grattix boxes use varying sizes of sediment to filter stormwater. Photo Credit: William Chen / ECOSS.
One of the innovative GSI solutions that are being featured at Equinox is the Grattix box. Essentially a rain garden in a box, the Grattix allows businesses to benefit from the filtration capabilities of rain gardens without having to dig up their property. These nature-based roof downspout filters remove zinc, copper and other pollutants from roof runoff, and can work in small spaces.
And what better way to learn about Grattix boxes than to go through the process of building one! Using Port of Vancouver’s design as a guide, ECOSS staff, multicultural contractors and members of the public convened at Equinox to learn by doing. From constructing PVC-pipe draining systems to planting native shrubs, just one afternoon of teamwork led to the completion of four complete Grattix boxes.
The event was a triple win for Equinox Studios, the contractors who have added Grattix systems to their repertoire, and the public who will be able to learn about new stormwater solutions.
These Grattix boxes’ native vegetation include X,Y,Z. Photo Credit: William Chen / ECOSS.
Grattix boxes enable the benefits of rain gardens on business properties. Photo Credit: William Chen / ECOSS.
These Grattix boxes are only the beginning of ECOSS’ vision for an industrial-scale demonstration site. Other cutting-edge solutions for stormwater management to look forward to are permeable pavement, vegetated walls, large cisterns and more. Stay tuned!
Learn more about the Equinox demonstration site!
Come to the Equinox Very Open House on December 14th at 6 pm. ECOSS and others will be at the event and can provide tours and information.
Thank you Aspect Consulting, PureBlue and Equinox Studios for supporting this work.
Additional support for the Equinox GSI project was provided by the Boeing Company, King County Flood Control District, BNSF and the 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.