Build. Span. Connect.


Seattle Bridge has a unique background in the design, fabrication, and installation of suspension bridges and other structures that involve remote-area installation, rigging acumen, or both. In addition to helping to scope and build suspension and cable-stay bridges, we perform the following tasks:

Bridge Inspections: Over time, all bridge structures experience wear, tear, and damage, whether in the form of corrosion, settling, racking from wind and flood events, or damage caused by collisions or vandalism. Seattle Bridge performs rigorous bridge inspections and evaluations, including steel section weathering analysis, surveying, and–where necessary–NDT testing.

Kapalua 3 blueprint

DesignSeattle Bridge Senior Engineer Al Highberger (PE) is personally responsible for stamping the plans on upwards of 50 cable bridges, and the Seattle Bridge team has a wealth of personal, hands-on experience with siting, scoping, fabricating, and installing these structures. Our multidisciplinary approach incorporates input from our own engineers, fabricators, and builders to produce designs that are efficient, economical, and long-lasting. We have particular expertise in projects for remote or environmentally-sensitive areas.

On a case-by-case basis, we may engage outside engineering firms with intimate understanding of our means and methods, carving out design/engineering as one contract and construction as a separate contract.  Our bridges meet the standards, based on Client requirements, of the American Institute of Steel Construction (AISC), International Building Code (IBC), Americans with Disabilities Act (ADA), American Association of State Highway Transportation Officials (AASHTO), and the American Concrete Institute (ACI).

Photo: Martin Walz.

Bellevue suspender bars fabricated and ready to ship.

Fabrication: Seattle Bridge operates a full-spectrum metal fabrication shop in Seattle, Washington, with hydraulic ironworking machinery, plasma cutters, saws, and welding equipment for ferrous and non-ferrous materials. We specialize in the welding and fabrication of A588 weathering steels and A36/A992 steels per the AASHTO/AWS 1.1 “Structural Welding Code” appropriate for vertical welding and structures; please note that the AASHTO/AWS D1.5 Bridge Welding Code specifically applies to welded highway bridges and is not applicable for Seattle Bridge structures. Seattle Bridge has certified welders and NDT Level III testers on staff.

Hot Riveting: Our own Steve Howell has, through trial, error, and personal obsession, rediscovered the art of riveting. He has been featured in a History Channel film about the possible failure of rivets on the Titanic, been flown into Collie, Australia to consult on historic recreation of a riveted bridge, and performed his riveting act at blacksmithing get-togethers all over the U.S. Here’s a glimpse into what he does and how he does it.

Photo: Martin Walz III

Ken Gilman and Austin Thompson completing superstructure installation.

Field Services: Seattle Bridge specializes in construction activities in remote and environmentally sensitive areas using traditional tools, appropriate technology, and innovative methods. Rapid, low-impact, and trouble-free installation is only possible when the structure is tailored to site logistical constraints, meticulously fabricated, and test-fitted during production. We have staged to construction sites using trucks, container ships, helicopters, pack stock, narrow-gauge rail, ATVs, and backpacks; once there, we perform excavation and grading, concrete forming and placement, steel erection and welding, rigging, and whatever else is needed.