Place of Circling Waters Habitat Restoration
Hart Crowser was awarded a ”Best in State Gold Award” in the social/economic value category of the ACEC Engineering Excellence Awards. We were one of only 5 gold winners out of 45 state entries.
The Place of Circling Waters project represents the Port of Tacoma’s largest habitat restoration, constructing just under 30 acres of new and restored habitat area adjacent to Hylebos Creek. The project was much more complex than most habitat restoration projects, requiring a significant 255,000-ton remedial excavation clean-up component prior to habitat construction, while also fulfilling five separate habitat mitigation obligations through a single construction project. Project design required trade-offs between cleanup and mitigation requirements, including balancing an unusually large number of conflicting environmental, geotechnical, civil engineering, landscape, and regulatory criteria.
Restoring this former gravel mine and inert waste disposal site to its natural state allowed the Port to recognize the benefits of this extremely valuable intertidal habitat at the mouth of Hylebos Creek. At high tide, water flows from the creek into the newly-created intertidal zone and stream channels, creating resting and feeding areas for juvenile salmon as well as habitat for native plants, water birds, and other wildlife. This is why officials with the Puyallup Tribe of Indians selected the site’s Twulshootseed name, kal’-ka-lukw-al-kwo’, which means “Place of Circling Waters.”
Besides creation of valuable intertidal habitat, the project also included new upland habitat areas and buffers that were landscaped with over 35,000 native trees and shrubs. To fill a steep ravine left from past aggregate mining, the team reused 70,000 cubic yards of on-site soil, including an innovative rock buttress at its base to address slope stability and groundwater seeps.