(continued from page 1)
stormwater runoff, a failing shoreline bank, and soil contamination. Besides providing a sustainable design, the Port of Tacoma wanted to know what the construction and maintenance costs would be for the site using traditional versus green infrastructure. The team’s design goals were to maximize the functionality of the site while increasing marketability for the Port of Tacoma. Although the site was encumbered by utilities and existing structures, the design integrated sustainable features that met treatment and drainage design requirements while providing attractive site amenities. The design also minimized site disturbance to address soil contamination concerns. The resulting proposal provided an efficient site design with redundant water quality benefits to fortify ecological connectivity and function in this industrial environment. The building design incorporated a green roof with native grasses selected for their hardiness and a soil mix appropriate for project goals. Rainwater harvesting was proposed as a stormwater strategy to help offset the need for added site interventions and provide water for building uses, such as wash-down or periodic green roof irrigation. The site layout maximized space available for port operations and screened it from the roadway with a constructed wetland. Site grading was minimized so that contaminated soils could be capped with concrete pavement and serve as a materials laydown area. The proposed bulkhead provided water access while serving as a “cut-off” to soil contamination leaching into the waterway. A perforated underdrain was designed to collect groundwater blocked by the bulkhead and treat the water for high pH via a cartridge filter manhole before discharging to the waterway. Riprap was proposed to be removed and replaced with a stabilization mat. The vegetated stabilization mat of articulated concrete blocks was planned along the shoreline to mitigate shoreline degradation, as well as enhance fish habitat at the slope toe. Along with the sustainable features and design that were submitted to TGIC, the team wanted to provide a way for the jury to realize how sustainable the proposed team’s design was. The team introduced Envision, the sustainable infrastructure rating tool, as a way to measure the design. BergerABAM has been applying Envision to projects since its inception in 2012 by the Institute for Sustainable Infrastructure. Envision regards Tacoma’s forward thinking, encouragement of sustainable design, and engagement of the public as important measures of sustainable design. The majority of the winnings that the team received were donated to Adopt A Family and the ASCE Sustainability Committee. The money will help support the activities to promote sustainability in the community. In the past, the committee has hosted events at local schools and will continue providing a scholarship to students to attend conferences. For more information on TGIC, visit http://www.cityoftacoma.org/cms/One. aspx?portalId=169&pageId=68259
Part of Team 303 included six BergerABAM employees.
2
To learn about participating with the ASCE Seattle Sustainability Committee, visit https://sites.google.com/site/ asceseattlesustainability/home.