- North Creek Culvert Removal
North Creek Culvert Removal
On January 27, 2022, the City held a Council Study Session regarding the proposed North Creek Culvert Removal and Replacement project at Harborview Drive. The primary project goal is to further improve fish passage and expand access to high quality salmon spawning and rearing habitat by removing the partial fish barrier as identified by the Washington State Department of Fish and Wildlife (WDFW) and included representatives from the Washington Department of Fish and Wildlife (WDFW), the Puyallup Tribe of Indians, the Gig Harbor Commercial Fishing Club, and Harbor WildWatch.
The outcome of the Study Session included proceeding with a professional services contract to prepare an alternatives analysis and Feasibility Study. The City contracted with Parametrix in June 2022 to proceed with the alternatives analysis, which included receiving input from stakeholders, reviewing potential permitting issues, preparing renderings for each alternative, and preparing cost estimates for each alternative.
The City and Parametrix completed their analysis and presented the findings to stakeholders on November 8, 2022 meeting. At the November 17, 2022 Council Study Session, Staff and Parametrix presented the findings of the alternatives analysis. The Feasibility Study shows renderings and costs for Alternative 1 (bridge) and Alternative 2 (culvert) plus a cost estimate for the re-alignment of the "unnamed creek" along the Wastewater Treatment Plant to North Creek. At the end of the November 17, 2022 Study Session, Council selected Alternative 1 (replace the culvert with a bridge) and directed Staff to proceed based on the alternatives provided. The 2023-24 Budget provides for the design and permitting of Alternative 1.
With this direction and the dedicated 2023-24 Budget to fund the design and permitting of the Project, the City desired to apply for a National Culvert Removal, Replacement, and Restoration Grant with the Federal Highways Administration. This grant could provide up to $4,000,000 in construction funding for this project. The City eagerly awaits the outcome of the grant application and will post the results once they are known.
The project will replace an aging 6-ft x 6-ft x 146-ft concrete box culvert that conveys North Creek under Harborview Drive. The culvert is located along the apparent natural flow path of North Creek. The current box culvert was originally constructed prior to 1970 and supports Harborview Drive on a soil fill prism that is approximately 22-ft in height and extends approximately 400 feet in length between the natural topography of the creek valley.
This current fish passage barrier is a water surface drop during most flow rates, and acts as a complete velocity barrier to juveniles, and a partial velocity barrier to adult salmon over a range of flows. This is a function of the culvert slope, hydraulic head over the range of flow rates, and the total length of 146 feet with no habitat variability within the concrete box.
The downstream habitat is located in the tidal zone of the estuary of Gig Harbor. In this area, the floodplain is partially occupied by a remote site incubator (RSI) that is used to rear chum salmon. The project will relocate the RSI out of the floodplain and restore the total floodplain width.
To improve fish passage at this location, a new crossing to safely convey the 100-year flood and provide suitable velocity and depth over a range of flows to allow use and passage by juvenile and adult salmonids. The project will remove the culvert and soil fill prism, replacing the crossing with a 45-ft x 85-ft bridge deck that will carry two lanes of traffic, pedestrian sidewalks, and utilities, including water, sewer, and electrical. In doing this, the new crossing will provide additional benefit as a wildlife corridor and can be designed to include a pedestrian undercrossing under the road along the stream bank to connect Donkey Creek Park, as was also done at the downstream crossing at North Harborview Drive.
The bridge will be supported on abutments that are spaced wide enough to accommodate the 100-year flood and the estimated 2080 climate change flood and include a pedestrian pathway under the bridge and above these calculated flood elevations. The width and slope of the restored stream channel through the new crossing will be developed with the accepted design methods and guidance put forth in the Washington Department of Fish & Wildlife Water Crossing Design Guidelines (WCDG) that is the current standard for all stream crossing projects in Washington State. Bridge and road elements rely on the WSDOT Road and Bridge Design Manual and the Stream Design Guidelines (WSDG, 2013).
In January 2018, the Washington State Legislature passed the Streamflow Restoration Act (RCW 90.94) to help support robust, healthy, and sustainable salmon populations while ensuring rural communities have access to water. This project is located in Water Resource Area (WRIA) 15. The draft WRIA 15 Watershed Plan (2021) responds to the Streamflow Restoration Act and establishes a balance for offsetting and reducing consumptive water use and maintaining flows in the streams to enhance watershed health.
The project site is located immediately upstream of the tidally influenced reach of North Creek. In 2013, the City designed and constructed the replacement of the previous downstream-most barrier in the watershed when they built the North Harborview Drive Bridge over North Creek.
The removal of the culvert and construction of the bridge will reconnect 3,800 linear feet of North Creek's stream corridor to the estuary of Gig Harbor and allow transportation of spawning gravel, sediment and large woody material to be transported to the estuary, and restoring the historic patterns of the watershed. It also allows for restoration of the streambed and slope through the crossing, removing the fish barrier and allowing upstream migration of adults to access the new spawning areas.These upstream reaches also provide rearing and refugia for juveniles across their life stages before migration. This project will meaningfully restore fish passage for anadromous fish: this segment of the stream and the associated riparian corridor is high quality and undeveloped, offering spawning and rearing habitat for anadromous salmonids and other aquatic and terrestrial organisms that utilize the watershed. The majority of the land located in this reach of stream is undeveloped and owned by the City, acquired for the purpose of conservation and preservation. The riparian corridor is intact providing shade and cooler water temperatures. The stream reach promotes health and undisturbed geomorphic processes.
Background and History
The City of Gig Harbor is built upon the homelands and villages of Indigenous Peoples of the region better known as a band of Puyallup Tribe of Indians called sx̌ʷəbabš (translated: “swift water people”). The land surrounding the estuary of North Creek was the location of a long house of the sx̌ʷəbabš band of the Puyallup Tribe of Indians and the area was of vital importance to the sx̌ʷəbabš for salmon fishing, clam and oyster cultivation, and canoe carving.
On February 22, 2021, the City Council approved Resolution No. 1199 that renamed Austin Estuary Park and designated the txʷaalqəł Estuary area in honor of the sx̌ʷəbabš band of the Puyallup Tribe of Indians. In the Lutshootseed language of the Puyallup Tribe of Indians, txʷaalqəł means "place where game exists".
On September 15, 2022, the raising and unveiling of the "Our Fisherman, Our Guardian" Honoring Pole, carved from a beautiful hand-picked redwood log by artist Guy Capoeman, President of the Quinault Nation. It depicts a Salish fisherman holding a huge salmon - in Capoeman's words, 'The One with All, the Ancient Ancestor". For more information view article by Gig Harbor NOW.
Prior to the 1920s, the North Creek basin was mostly free flowing (did not flow through man-made structures). However, as the local vehicle transportation system began to develop, the state of Washington and Pierce County placed roadways over North Creek and installed culverts and one bridge over North Creek. Eventually the bridge was replaced with a culvert. While these culverts were maintained to allow the Creek to flow through them, the culverts either partially or fully blocked the migration of anadromous fish.
Until the early 1050s, North Creek (formally known as Donkey Creek) flowed freely from its headwaters to Austin Estuary and into Gig Harbor Bay. In the 1950s, much of the estuary was filled in and a series of culverts were installed to divert the Creek through town. The three culvert removal projects (one completed, two planned) intend to daylight North Creek, restoring it and associated estuarine habitat to its near natural condition.
By the late 20th century, the Washington State Department of Fish & Wildlife (WDFW) identified multiple culverts located in what is now the City's right-of-way that were either partial or full fish passage barriers along North Creek. These identified barriers restricted access by anadromous fish to substantial undisturbed and valuable available habitat and spawning areas as identified by both WDFW and the Wild Fish Conservancy. The City recognized the importance of re-establishing access by anadromous fish to this habitat and spawning areas and began implementing both the removal of these blockages and the preservation of much of the undeveloped land that surrounds North Creek.
The project has been developed through /DocumentCenter/View/4132 conceptual design. A feasibility study presented and evaluated a series of alternatives. Preliminary design will begin in March 2023. The design will progress through standard development review, creating 30%, 60%, 90%, final design to bid-ready construction documents. The end date of the design process is expected to align with environmental compliance and permitting activities and anticipated to be completed in 2024. Construction is planned for 2025 to 2026. While the construction will only take one year, targeting all in-water work to be completed in a single season to avoid the need for winter stream flow bypass, another season is scheduled incase of delays in acquiring materials.
Public and stakeholder engagement has been a key component of the feasibility planning for this project. After completion of the first culvert replacement/bridge construction project that daylighted Donkey Creek under the new North Harborview Drive bridge, public support has been high for continuing to daylight North Creek. Outreach and engagement will continue through the design and environmental processes, with public noticing continuing through construction. The City conducted outreach with individual stakeholders and hosted two public meetings to share progress with interested parties. The meetings occurred in January and November 2022. The participating stakeholders shared perspectives and comments were incorporated into the design. The consensus is to provide the largest feasible opening to restore natural stream processes that aren't confined by the crossing. The City is committed to continuing the design review process with the stakeholders, including hosting additional engagement meetings during the design process and one immediately prior to construction.
The Puyallup Tribe is participating in the design review process and has provided comments related to the site's cultural significance. These comments will also support the cultural resources review and preparation of the Section 106 permit application.
Primary Project Contact
Dean Zavack, P.E., Senior Engineer