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Approximately a mile west of downtown Portland, general contractor R&H Construction recently finished an atypical project: installation of a prefabricated pedestrian bridge.

鈥淚t’s unlike anything I’ve ever built, that’s for sure,鈥� R&H Construction superintendent Chuck Roberts said of the Barbara Walker Crossing project.

The $4 million bridge connects two stretches of the 30-mile-long Wildwood Trail above West Burnside Road.

鈥淲orking up here on Burnside with traffic has been an epic nightmare,鈥� Roberts said. 鈥淧eople get in a real hurry coming down and back and forth across this hill. The structure itself was built in a shop out by the airport, but once the structure was built, getting the structure 鈥� down here was quite an achievement in itself.鈥�

Supreme Steel fabricated the main span in three separate sections. The first one was transported from the firm’s Northeast Portland plant to the project site Oct. 7 and then flown into place atop the concrete support column with a crane the same day. The second and third pieces came two days later, at 4:30 a.m. to avoid rush hour traffic as much as possible.

鈥淲e set them up right here and we had this lane closed, but we kept the other two lanes flowing,鈥� Roberts said. 鈥淭hen we put the (two pieces) together, welded them all back together, and added a bunch of members that were needed.鈥�

Crews soon resumed construction, and the 125-foot-long section of the main span was moved into the middle of the roadway for erection.

鈥淎t that point that piece weighed about 31,000 pounds,鈥� Roberts said. 鈥淲e got it up and swung it around, missing power poles and trees and other stuff, and we got it into place.鈥�

Then the structure was suspended from the crane next to the first section while ironworkers completed welds.

鈥淥nce we had it in the air we had to join it with piece one and get all that welded back together,鈥� Roberts said. 鈥淭hen we had a bunch of bracing welded on prior to letting the crane go on Saturday night. It was pretty interesting.鈥�

KPFF Consulting Engineers performed the engineering work needed to make the bridge structurally sound.

The new bridge is 178 feet long as measured at the center of its curvy deck. Its basic structure, as designed by artist Ed Carpenter, is a tri-chord truss made from steel tubing. It has a rust-colored and painted surface with elements intended to represent the sword ferns and vine maples found in surrounding forests.

Ground was broken in March. Along the way a series of micro-piles were drilled to shore up a single, large concrete support column on the south side of the roadway. The bridge rests atop this column, anchored at each end by new concrete abutments placed in the hillside on each side of the roadway.

The new bridge opened to the public on Sunday with a celebration.

鈥淚t’s been really tough keeping people out of there during the summer building this thing,鈥� Roberts said. 鈥淚t’s been quite a challenge and I can tell you that after running back and forth across this road as many times as I’ve had to during this project, that this thing is needed beyond words.鈥�

The project was paid for primarily with money from a crowdfunding campaign carried out by the Portland Parks Foundation, along with grants and some public dollars.