King County’s Georgetown Wet Weather Treatment Station (WWTS) earned the coveted “Platinum” designation from the Institute for Sustainable Infrastructure’s Envision rating system. This is the first Platinum-awarded Envision project in Washington and recognizes the County’s commitment to sustainable communities and the environment.
The Georgetown WWTS project in Seattle’s Georgetown neighborhood will treat up to 70 million gallons of combined wastewater and stormwater per day during storm events to protect the Lower Duwamish from pollution.
The Envision award was received in 2018 based on project plans. As the project moves towards completion, we are seeing the results that earned that designation.
The Institute for Sustainable Infrastructure’s Envision rating system assesses sustainability in five categories: Quality of Life, Leadership, Natural World, Resource Allocation, and Climate and Resilience. Activities in these areas contribute to positive social, economic, and environmental impacts for a community during the planning, design, and construction of projects.
King County is committed to sustainable construction practices as well as sustainable facilities.
“Our agency believes in being an industry leader on sustainability,” notes Heidi Sowell, Sustainability Program Manager. “We decided to pursue Envision certification, even though it was relatively new at the time of project design, based on the clear ties to infrastructure sustainability. This fits in well with the other sustainable activities we do like our green building practices, clean energy, and recycled water.”
“The Envision wholistic approach to infrastructure sustainability integrates well with King County’s standard approach to project development,” adds Tina Hastings, Project Manager from Jacobs, King County’s consultant on the project.
Here’s what we did to achieve gains in each of the Envision categories:
Quality of Life
- King County partnered with DIRT Corps and Stone Soup Gardens to build green stormwater infrastructure – a rain garden and two cisterns – at a local grocery store.
- The project team worked with the community to get grant funding to support the implementation of improved, safer pedestrian connections to the Duwamish River, as well as funding to support the construction of a 135 foot-long and 12-foot-high green wall on the block along East Marginal Way and Eighth Avenue, which will help with dust and air quality issues in the area.
- King County partnered with Nature Consortium and Seattle Public Schools to teach fifth graders at Maple Elementary about water conservation and to create art for the construction fence.
- We designed public space in the front of the building, improved sidewalks, green stormwater infrastructure and a large room inside that allows for educational opportunities.
- Public art will enhance the buildings and help people learn about stormwater, including a “Rain Monument” and “Theater of Storm” which visually recreate the rain and treatment processes, allowing the community to “see” what happens inside the industrial facility.
Leadership – Providing for Stakeholder Involvement
- The design of the project was influenced by a community Design Advisory Group, community meetings, and community surveys.
- King County staff have worked with the community throughout the project, providing regular project updates on construction progress, including notices about lane closures and traffic impacts.
Resource Allocation
- We looked for ways to recycle and reuse project materials during demolition and construction, aligning with the County’s Strategic Climate Action Plan, which has targets for zero wasted resources with economic value by the year 2030.
- We removed five buildings from the site and about 7,000 tons of contaminated soil. We were able to salvage concrete and old growth timber beams from some of the demolished buildings for reuse.
- We used regional materials for construction – avoiding climate impacts on shipping them from elsewhere. Of the materials we used, about 90 percent were regionally sourced.
Natural World
- We managed stormwater properly during construction.
- Green Stormwater Infrastructure (GSI) was added to the project’s design, including a green roof and rainwater harvesting. GSI uses natural drainage solutions like plants, trees, and soil to soak up rain.
Climate and Risk
- The station was raised two feet to account for climate change and projected sea level rise.
- Rainwater is stored onsite for irrigation to save potable water during dry months.
You can visit these links to take a virtual tour of the Georgetown construction site in English or in Español (Spanish).
