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Completion is finally in sight for Multnomah County’s Central Courthouse project.

With delivery scheduled for spring 2020, the three-year process to erect a new 17-story, $325 million courthouse building on Portland’s waterfront is entering the home stretch as the number of craft workers on site starts to ramp down significantly. From a high three months ago of some 350 workers on site each day, that figure is now down to just over 200 as rough-in has been completed and finish work accelerates.

鈥淭he biggest period was about three or four months ago because you had everything happening,鈥� said Justin Paterson, project manager for construction manager/general contractor Hoffman Construction. 鈥淵ou were still doing rough-in on the upper floors, but now the wet-side mechanical guys are pulling out and the dry-side mechanical guys are pulling out from the rough in, and they’re down to a couple of people.鈥�

Architecture firms SRG Partnership and CGL RicciGreene designed the 461,000 square foot building, which will feature 44 total courtrooms on floors eight through 17. Additional small claims, traffic and other high-volume court functions will be located in the renovated historic Jefferson Station building at the southwest corner of the project site on Southwest First Avenue and Jefferson Street.

The project is aiming for a Leadership in Energy and Environmental Design (LEED) gold rating.聽The new facility will replace the old county courthouse on Southwest Fourth Avenue, which was completed in 1914 and is considered by the county to be functionally obsolete. The older building does not meet modern seismic codes, and is considered at high risk in case of an earthquake.

The new courthouse will be an estimated 46 percent more efficient than a conventional code building, and will use energy saving strategies that include radiant slab heating and cooling, a high-efficiency chiller plant, displacement ventilation, radiant panel heating and cooling, thermal storage in fire and rainwater tanks and chilled beams. A rooftop solar array will help generate power for the building.

Another notable feature is the limestone cladding used on the building exterior and on the interior walls of the main lobby. The cladding was fabricated by Columbia Stone and is being installed by the company’s own personnel.

Further, because the building is designed to withstand a significant earthquake, viscous dampers akin to shock absorbers have been placed throughout floors eight through 17, while outsized concrete and steel structural members anchor its framework.

This is most evident in the main entry, where massive octagonal structural columns serve both a functional and aesthetic purpose.

鈥淚t’s not hollow on the inside, it’s solid concrete and it’s poured exactly like that,鈥� Paterson said. 鈥淚t’s got a wide-flange beam on the inside of it and then a rebar cage and basically a steel shell goes around that. We build that in two halves, board form line it, stand it up, bolt it together and then the concrete is pumped in from the bottom.鈥�

Once the head pressure falls too low, he added, which is right around the 40-foot mark, crews quickly switch over and start pouring from the top. 鈥淵ou’re trying to make the gap, the seam, disappear,鈥� Paterson said. 鈥淪o they have to move pretty quickly.鈥�

There’s the new, and there’s also the tried and true. The renovation of the historic, three-story Jefferson Station building falls squarely in the latter category. The first reinforced concrete structure built in Portland, the old building is being refurbished for use as high-traffic courtroom space, but because of its historic designation the original fa莽ade has been retained even as the building has been physically connected with the new courthouse tower.

Another original touch, however, is purely for show.

A 20-ton-capacity gantry crane dating to 1909 will remain on its original track on the top level of Jefferson Station, still able to roll back and forth smoothly on its track. That discovery, however, took a bit of work.

鈥淚t (the crane) was actually still sitting on a little stub of rail that was still there,鈥� Paterson said. 鈥淲e do a lot of work for Sound Transit in Washington, so we called them up and said 鈥楬ey, where do we buy railroad track?’ And they said 鈥極h, no problem, we’ve got a railroad track company,’ and he sent me a name.鈥�

A Hoffman engineer sent the firm a profile of the needed track and a photo of the Jefferson Station crane. The response was somewhat unexpected.

鈥淥ne of our engineers sent them a profile of it and a picture of it and the guy said 鈥榊ou know what? We actually have some of that in our yard.’ So they shipped it down here, it was actually pretty cheap, and we installed it ourselves.鈥�

As it turns out, the century-old crane was built to last.

鈥淲e just connected the rail together and some guys got up there and unlocked the wheels and the damn thing still rolls,鈥� Paterson said. 鈥淚t’s got a chain fall on it and they started pulling on the chain and it traveled on its own.鈥�