Port of Tacoma wins the 2021 Environmental Stewardship Award
The Washington Public Ports Association is pleased to recognize the Port of Tacoma’s outstanding environmental stewardship displayed in their Upper Clear Creek Mitigation Site project with a 2021 Environmental Stewardship Award. You can learn more about their project from their award application proposal below.
The Project
The Upper Clear Creek Mitigation Site (UCCMS) project is a 40-acre wetland restoration project located within Washington State’s lower Puyallup River floodplain. The purpose of the project is to restore a functioning floodplain ecosystem within the Port’s UCCMS. This included reconfiguration of the Clear Creek channel, new back channels and ponds through the site; reestablishment of the connections between the creek and the surrounding floodplain wetlands; and restoration and creation of a forested mosaic wetland and forested buffer.
Mitigation Bank
The UCCMS provides the Port with mitigation credits for future Port development projects that require mitigation for unavoidable impacts to aquatic resources and fish and allows the Port to sell those credits to third parties that need mitigation credits. Combining wetland and fish conservation mitigation into a single mitigation bank in Washington State is relatively new and as a result the approval process was long and complicated, in part due to ongoing development of methods used to determine credit values for mitigation bank sites. For the UCCMS, conversion rate ratios established by the US Army Corps of Engineers (Corps) and Washington State Department of Ecology (Ecology) were used to determine wetland mitigation credits. The Port utilized the National Oceanic and Atmospheric Administration’s (NOAA) National Marine Fisheries Service’s (NMFS) Habitat Equivalency Analysis (HEA) model to calculate habitat gains for the purpose of determining fish conservation credits.
The project received final approval on June 24, 2020 from the Ecology, Corps, and NMFS. The Upper Clear Creek Mitigation Bank is the Port’s first mitigation bank, the first of its kind in the Puyallup River watershed, and only the second joint wetland and fish conservation bank in Washington state. The mitigation bank is expected to generate 12.56 wetland acre-credits and at least 273.16 fish credits over a ten-year performance monitoring period. With the construction completed in 2016, the Bank has already released 3.77 wetland acre-credits and 81.99 fish credits with additional credits to be released upon the approval of the Year 1 and Year 3 monitoring reports that have been submitted for review.
Amazing Habitat Creation
Habitat elements created within the floodplain, including installation of large woody material and habitat snags, grading of hummocks (i.e., earthen mounds), and excavation of new channels, rearing ponds, and alcoves, are creating habitat complexity and provide increased habitat quality for fish, wildlife, macroinvertebrates, and microorganisms.
Created 4,600 linear feet (1.43 acres) of new creek channel
Enhanced 1,600 linear feet of the existing creek channel by creating alcoves and habitat structures
Re-established 7.0 acres of wetlands by removing fill materials and planting native plant communities
Rehabilitated 26.4 acres of existing wetlands by restoring riverine floodplain processes
Enhanced 4.8 acres of upland riparian buffer habitat by planting a native forested plant community
Installed over 197 large woody material habitat structures within restored channel, ponds, and floodplain
Planted over 145,000 native plants in addition to seeding native grasses and emergent plants
Provided microtopography that supports a diverse range of hydroperiods
Restored natural floodplain processes and connectivity
Created an additional 29.89 acre-feet (2-Year flood) of flood storage volume within a FEMA floodplain and floodway
Outcome and Results
The UCCMS construction was completed in 2016 and combines the 28.64-acre mitigation bank to another 12.59-acre Port-owned mitigation project, creating more than 41 acres of contiguous restored habitat in the Clear Creek floodplain with the option for future expansion. UCCMS is in Year 5 of its 10-year performance monitoring period and is currently meeting or exceeding all performance standards. Clear Creek is the Puyallup River’s last freshwater tributary before entering Puget Sound’s Commencement Bay. Clear Creek is vital habitat for migrating salmonids because it provides the last opportunity for off-channel rearing and foraging before transitioning to saltwater. Recent studies with Puyallup Tribe Fisheries, South Puget Sound Salmon Enhancement Group, USFWS, and the Port have documented all three Endangered Species Act (ESA)-listed salmonids (chinook, rainbow/steelhead trout, bull trout) in the Clear Creek system. UCCMS is home to several wildlife species including resident trout, beavers, coyotes, deer, small mammals, and over 65 different species of songbirds, waterfowl, and raptors. This site adds 41 acres to the Port’s habitat portfolio, totaling over 213 acres of habitat the Port has helped to build or preserve.