The view from Interstate 5 at the south end of downtown Portland, OR, is in the midst of a transformation. Two years ago, drivers saw a river, trees, houses and lots of buildings (most topping out at just a few stories).
Today, it’s a nearly-complete 16-story, 400,000-sq.-ft. medical/retail building owned by Oregon Health and Science University (known as Building One), cranes, scaffolding and the mid-tower of an aerial tram that will eventually carry passengers between Building One and OHSU’s main campus on Marquam Hill.
Scheduled to begin operation this December, the 3,300-ft. tramway will feature two 80-passenger cabins.
“Cycle time is 277 seconds for 13 trips per hour for a theoretical capacity of 10,104 persons per hour. The maximum travel speed is 2,000 feet per minute,” said Kevin Young of Doppelmayr CTEC, explaining that the two cabins will run opposite each other so one will be at the top and one at the bottom during the load/unload cycle.
Doppelmayr, a Switzerland-based company with several international branches, is charged with the design and installation of the actual tramway equipment, while Kiewit Pacific Structures of Vancouver, WA, serves as the general contractor/construction manager on the project.
A long list of subcontractors also are lending their expertise to the project, including Fortis Construction and Thompson Metal Fab. Architect Sarah Graham of Angelil/Graham/Pfenninger/School designed the structure. Portland Aerial Transportation Inc. (a non-profit group charged with making sure the tramway meets rigid design and architectural standards), selected Graham through a design competition process in March 2003.
“This will be a world-class [structure]” said Bruce Patterson, Kiewit’s project sponsor, explaining that the company is building a total of three separate tram structures — a lower station, a mid tower and an upper station.
Patterson said Kiewit’s expertise in heavy structure and bridge work meant the company’s workers were ideally suited for the project.
“That is how we were able to sell ourselves to the city,” he said.
All-in-all, the tram used 1,300 tons (1,179 t) of concrete, with 1,500 cu. yds. (1,147 cu m) of footings and 150 drill shafts, Patterson said. Crews used very conventional equipment to build the stations, including a Manitowoc 222 Crawler Crane, a Liebherr 550 and a Demag Camel Crane.
“We’re [also] using the usual selection of man lifts and fork lifts,” Patterson said. “…Just small, mobile things.”
The lower station, in addition to serving as the load and unload point at Building One, houses the tram’s operational machinery. Measuring in at 196 ft. (60 m), the mid-tower (positioned just west of S.W. Gibbs and S.W. Moody streets in Southwest Portland) is used for structural support.
Kiewit used five-eights-in. plate steel and 10,000 PSI concrete to build the structure. With the exception of some finish work, the lower station and the mid tower are essentially complete, Patterson said.
Construction of the upper station also is well underway. Eventually, the station will feature 7,000 sq. ft. (650 sq m) of floor space and a pedestrian bridge connecting the structure to an OHSU patient care facility.
In mid-July, crews worked on getting the station’s support legs up in preparation for Dopplemayr’s installation of the tram rope.
Crews will spend the next two months building additional support structures at each intersection from Water Street (where Building One sits) to the base of Marquam Hill, said David Gonzalez of the Portland Office of Transportation.
“Once the tramway equipment is installed at the top terminal, we will be able to start the installation of the wire ropes,” Young said. “[This process] will take five to six weeks.”
The tramway will use a total of five ropes — four 49mm Z-lock trap ropes, measuring 4,593-ft. (1,400-m) long, and one 34mm eight-strand haul rope, 2,300 m long. These ropes will be pulled onto the structure using a winch and 16mm wire ropes for installation, Young said. In addition, Dopplemayr is using temporary support structures to “keep the wire ropes out of the way of traffic,” he added.
This aspect, according to Young, is quite challenging.
“We need to keep traffic flow as close to normal as possible on the city streets and we cannot close I-5 or any state roadways. This is a residential area and the residents are going to be inconvenienced because of the structures and the lack of parking places,” he said.
Another major challenge: tight space, said Patterson.
“The work areas are very small. It is hard to get access without severely impacting OHSU’s operations,” he said.
But the challenges go beyond construction-related ones.
The tram project has been controversial from the start, in part because of money, in part because of aesthetics (some Portlanders, especially those living near the base of the mid tower, simply don’t want to see the structure out their kitchen windows). Costs have increased dramatically since the onset. Original estimates hovered around $15 million, but that’s only about a quarter of the amount officials are now estimating — most of which falls on the shoulders of OHSU.
“The escalation of the tram’s costs have been a bitter pill for OHSU to swallow because the university has footed most of the bill but has had little to say over management of the tram’s construction,” said Steve Stadum, OHSU’s chief administrative officer.
However, costs were contractually capped at $57 million earlier this year. OHSU is covering 27 percent, with the rest covered by two local improvement districts, the Portland Development Commission and North Macadam Investors (a local land development group).
Nearly $35 million goes to Kiewit, and another $10.5 million to Doppelmayr. Approximately $9.2 million is allocated to engineering costs, and the remainder is set aside for contingencies.
Despite the expense, involved parties, including OHSU, are excited about getting the tram up and running.
“The long-term benefits of the tram for OHSU and the region are almost incalculable,” Stadum said.
Some of those benefits include serving as a “catalyst for $2 billion worth of new investment” on Portland’s south waterfront and removing excess traffic from city streets, he added.
And Patterson suspects “people will forget the costs” as soon as they witness the results.
“I think it is going to be an excellent project,” he said.
CEG
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