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Barbara Walker Crossing
Submitting Company: R&H Construction

Location: Portland
Start Date: March 2019
Completion Date: October 2019
Owner/Developer: Portland Parks Foundation
Architect: Ed Carpenter Studio
Engineer: KPFF
General Contractor: R&H Construction
Subcontractors: A-Cut Above Concrete Cutting, Carlson Testing, Cascadian Landscapers, Chick of All Trades, Columbia River Contractors, Coulee Concrete Designs, Don Rhyne Painting, Green Brook Engineering, M&M Construction Services, PLI Systems Inc., Shiels Obletz Johnson, Supreme Steel, TerraCalc Land Surveying, Walker & Macy, Zavala

The Barbara Walker Crossing was crafted to prevent a tragedy long posed by the dangerous at-grade crossing for the estimated 80,000 hikers and runners who cross West Burnside from the Wildwood Trail.

The pedestrian bridge provides a safe connection between two of the Wildwood Trail鈥檚 most popular destinations, Hoyt Arboretum and the Pittock Mansion. An average 400 people crossed Burnside each weekend before the bridge, and 2,000 cross it now.

The crossing is named for the late Barbara Walker, a champion of trails, connecting parks and outdoor spaces. Portland Parks Foundation led the project, raising the money and hiring the designer, engineer and contractor. Portland Parks & Recreation, Portland Bureau of Transportation and Metro each provided money and bureaucratic and technical expertise.

The crossing is Portland鈥檚 first crowd-funded bridge, with more than 60 percent of the budget coming from more than 900 contributions from foundations, businesses and individual donors. The design and construction team donated countless hours of services early on in the design and development phase to ensure the crossing project was set up for success.

Featuring a walking surface crafted of fiberglass panels, the 180-foot bridge curves over Burnside with a 150-foot radius and is designed to blend into its natural surroundings. The sides of the bridge are highlighted by green branches that resemble ferns and evergreen needles and, over time, the unpainted steel will seal itself with an earthy, rust color that will further integrate it into its surroundings.

Among the project鈥檚 challenges, the bridge needed to be lifted into place quickly to minimize disruptions to Burnside, one of the busiest roads in the region and a major artery for emergency services. Once the bridge鈥檚 fabrication was complete at the warehouse, it was cut into three sections weighing 5.5 tons, 8 tons and 10 tons each, and transported to the site over five days.

Another challenge was access to the site. The project team elected to deliver the loads via Southwest Barnes Road through the historic, 230-foot Burnside Tunnel. Pre-engineering revealed the load would fit through the tunnel with a margin of just 12 inches on either side.

Extreme caution was taken to protect the public鈥檚 safety and limit the amount of disruption to nature. 鈥淎t one point during construction there were birds that were nesting in trees near the site. Precautionary measures were put in place to ensure these birds were not disturbed,鈥� R&H Construction said.