homeWelcome, sign in or click here to subscribe.login




print  email to a friend  reprints add to mydjc  

July 27, 2023

6-year rehab faced many challenges

  • The work was divided into five phases, with both below-trestle and above-trestle work.
    Holmberg Mechanical


    Colman Dock was initially constructed in 1882. A lot has changed since then, especially over the last 50 years.

    The terminal was deemed “seismically deficient” in 2016 with concerns over how it would fare in the event of an earthquake. Entities involved, including WSF (Washington State Ferries), WSDOT (Washington State Department of Transportation), and others, capitalized on the revamp opportunity to create a more tourist-friendly terminal experience to provide a critical link for continued economic growth. That was a lot to ask for from a ferry terminal.

    Two contractors partnered in a joint venture to tackle the terminal, which is expected to provide transportation for 10 million passengers annually in Puget Sound. Hoffman Construction and Pacific Pile & Marine combined forces and resources to bring the city of Seattle the most efficient and beautiful ferry terminal seen yet. The design was focused on how to enhance the passenger's ride from beginning to end.

    HistoryLink image [enlarge]
    Colman Dock was built in 1882 and has remained active over the years. Shown in 1911 is Colman Clock, which will be relocated inside the new terminal.

    During the six-year modernization with a nearly half-billion-dollar price tag ($467 million to be more precise), the hurdles to overcome have advanced from its humble beginnings. This massive project started with the first of many challenges in that construction could not impede ferry service passengers that rely on Colman Dock annually. The work has been divided into five phases with both extensive below-trestle work, but also above-trestle work that included multiple buildings: a new passenger-only ferry terminal, a new terminal building built in two phases not to interrupt passenger traffic, a vehicle passenger attendant crew building, an entry building that runs parallel to the new Alaskan Way, and an elevated pedestrian connector connecting the entry building and terminal building.


    Holmberg Mechanical, a Puget Sound-based full-service mechanical contracting and engineering firm, was asked to provide the scope for the complicated long-term project and was chosen by WSF after several successful maritime upgrade projects, including the Elliott Bay Seawall project, Pier 62/63, Seattle Fire Department on Pier 59, and the Bremerton Naval Hospital.

    In the early stages of the project, Holmberg Mechanical crews worked in the pitch dark to accommodate the tide schedule removing old pipes and replacing them with new piping systems under the trestle. Randy Hart, Holmberg Mechanical's project foreman, created a safe working solution — utilizing pontoon boats and powered lift pods to adjust to the tide.

    “Two types of lift pods were utilized; one took the crews up to a working height of 13 feet, the other to a working height of 19 feet, 6 inches. The first one was mostly used on the outside of the trestle along the sides, whereas the second was used primarily below the trestle for installing five miles of main utility piping and supports for the project,” said Hart.

    “What inspired me was the need to work around the clock, with the tides and maximizing safety,” he said. “While working on the earlier seawall project, I observed far too much downtime waiting for tides and once the proper tide was achieved, the work had to be done as fast as possible to get the intended work complete before the water level was once again lost. All in all, safety was my main driver for dreaming up such a plan. To add a lift pod to a workboat has not only worked to perfection but since has been adopted by Valley Electric and we worked closely together on the project. The in-house design team allowed us to now work continuously from a plus-level tide down to a minus tide of 1 foot.”

    Another consideration that added layers of complexity was that the project had to remain open with uninterrupted service regarding traffic for vehicles and pedestrians, as well as other enormous construction projects occurring at the same time, like the removal of the viaduct. Crews on each job worked as one team to ensure safety and efficiency.

    To create the foundation of the new trestle for current and future vehicle holding, 7,500 tons of creosote-treated wood was removed from the water and replaced with 500 new steel piles and concrete to meet seismic and operating requirements. About 12,000 cubic yards of concrete was poured for the holding lanes on the trestle, which can now handle 611 vehicles, 185 more than before.

    The terminal building now faces the water with 4,200 square feet of floor-to-ceiling windows looking towards Elliott Bay and the city of Seattle. While passengers wait, they will enjoy 20,000 square feet of space, with room for 1,900 people maximum. There are four bathrooms with 24 stalls. A total of 1,400 cubic yards of concrete was poured for the new terminal building. The total amount of piping installed by Holmberg Mechanical was 27,000 feet.

    “I am proud of the team and the finished product we installed. It was a challenging project and Hoffman was a great GC for our success,” said Kelly Peterson, project manager for Holmberg Mechanical.

    There are two plazas with the new Colman Dock. According to the WSF, the agency asked two local tribes to name them. For the south plaza near Yesler Way, the Muckleshoot Indian Tribe named it slu?wi? — meaning “a canoe shortcut through the reeds.” The Suquamish Tribe is calling the north plaza by Columbia Street ?ulu?ali — meaning “a place traveling by water.”


    Seattle Multimodal Ferry Terminal at Colman Dock recently received regional recognition in the 2023 America's Transportation Awards, winning the Quality of Life/Community Development, Large Category.

    “This has been one of my favorite Holmberg projects to watch our teams build together,” said Jeff White, CEO and president of Holmberg Mechanical. “The complexity of the work, including all of the external factors we don't normally encounter. The team navigated wildlife including whale migration, working on skiff boats at night, dealing with inclement weather, and within specific tide schedules. All this and they maintained the critical path, stayed on budget, and delivered this project to Hoffman and PP&M with an award-winning safety record. This is something that makes me incredibly proud of everyone involved.”

    The new Colman Dock is part of the projected increase in tourism while also serving transportation needs for businesses and commuters. It will continue to aid as a maritime extension of the state's highway system.

    Angela White is the marketing and public relations manager for Holmberg Mechanical, a 74-year-old full-service contractor in Bellevue. Holmberg Mechanical engineers and constructs large-scale commercial projects such as high-rise, transportation, hospitals and hotels.

    Other Stories:

    Email or user name:
    Forgot password? Click here.