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The Burnside Bridge is gaining some much-needed upkeep, but even its overseer, Multnomah County, knows it’s only a stopgap.

The steel-and-concrete bridge, a vital connection between downtown Portland and the Central Eastside, is 93 years old. Crews are performing extensive concrete patches and repairs, removing rust and refinishing hundreds of structural steel beams. Also, sidewalks and ornamental guardrails are being refurbished.

鈥淭丑别 Burnside Bridge maintenance project is really sort of a Band-Aid project to get another 10 to 15 years out of the bridge,鈥� county public information officer Mike Pullen said. 鈥淢ultnomah County is considering doing a much bigger project to make the bridge earthquake-ready, and that could even involve replacing the bridge, so the work we’re doing in this three-year project involves concrete repairs, some repainting and a little bit of minor electrical work.鈥�

The project derived from the county’s 2015 Willamette River Bridges Capital Improvement Plan, which identified the Burnside Bridge’s structural and movable components needing major rehabilitation. The county put the bridge at the top of its list of priorities for near-term work, and bidding on the roughly $20 million project took place in early 2017. Springfield-based Hamilton Construction, the project’s general contractor, started work later that spring and is now expected to finish by the end of 2019.

Major issues that are being addressed include rusting steel truss members, cracked concrete, deck surface deterioration and outdated mechanical and electrical systems.

Crews began on the Willamette River’s west side, tackling concrete repairs and other work. West approach girders, bent caps and columns were all rehabilitated, along with steel support trusses.

Meanwhile, the west-side bascule pit and control tower were also renovated, and the span locks and motors also received attention. The west-side control tower, which normally houses the drawbridge operator, was emptied to perform a remodel and address water intrusion. Other issues were addressed in work done by subcontractor Pacificmark Construction.

On the top of the bridge, the deck and expansion joints were renovated, while sidewalks, guardrails and overhangs also were repaired as needed. Many of the issues being addressed were identified when the bridge was most recently resurfaced, Pullen said.

鈥淲hen they did that 10 years ago, they didn’t do anything underneath the bridge, and that’s where a lot of the repairs have been,鈥� he said. 鈥淚t’s the concrete mostly; they had nets underneath the bridge to catch the little bits of concrete that were falling, especially around the Saturday Market. One theme of things like this is that it is really a Band-Aid. If I were to show you other things like the Hawthorne Bridge in the late ’90s, in restoring that bridge they repainted every single thing and did new decks. With this, we didn’t invest too much, and when this side opens in February (the public) will notice improvements, but they’ll also notice these patches.鈥�

Masons with Pioneer Waterproofing apply exterior weather sealant to the concrete girders below the Burnside Bridge’s east end.

One new technology being used by subcontractor Pioneer Waterproofing to carry out concrete repairs involves injecting epoxy adhesive into holes in the concrete and then wrapping those areas with carbon fiber reinforced polymer. The polymer then dries along with the epoxy to create a stronger span than the original.

Other discoveries made during the project indicate that the bridge needs more attention.

鈥淭丑别re were a few things that are bigger scale,鈥� Pullen said. 鈥淭丑别y found a crack in the pier in the river that’s closest to the downtown side on the west side, so this summer we’ll be going in there and dewatering and basically bracing that crack with some steel that goes through the whole thing and tighten it up.鈥�