Traffic Challenges Contractor of Seattle Streetcar Project

Sept. 28, 2010

Seattle will soon be hearing the clang! clang! clang! of the trolley between downtown and Lake Union, as the result of a 1.3-mile, $50.5-million construction project now under way. The start of service won't come a moment too soon, given the crowded state of the city's streets.

Seattle will soon be hearing the clang! clang! clang! of the trolley between downtown and Lake Union, as the result of a 1.3-mile, $50.5-million construction project now under way. The start of service won't come a moment too soon, given the crowded state of the city's streets.

In May 2006, the city of Seattle gave Stacy and Witbeck Inc., the project's general contractor/construction manager, the notice to proceed with building a modern streetcar that will connect South Lake Union Park and the Fred Hutchinson Cancer Research Center to Westlake Center. The South Lake Union Streetcar service will feature three air-conditioned vehicles that can carry up to 140 passengers and will make several stops every two or three blocks along the route.

An estimated 330,000 riders will use the streetcar annually, according to city estimates.

"We're getting this train rolling," said Mayor Greg Nickels at a ground-breaking ceremony on July 7, 2006. "The streetcar is an investment in the future of Seattle. When it opens next year, it will connect thousands of people to the new jobs, homes and parks coming up in the South Lake Union neighborhood. It will also connect to other transit and help us create great urban neighborhoods in the heart of our city."

In advance of streetcar operations, the project includes relocating utilities, installing track, making roadway improvements, upgrading traffic signals, building a maintenance facility, and testing streetcar vehicles. Stacy and Witbeck is self-performing roadway demolition, excavation and track work.

Key costs of the project include the $31.6-million construction contract and $9 million to purchase the three vehicles.

Patterned on Portland

The design of the South Lake Union Streetcar is patterned after Portland's Central Streetcar system, which Stacy and Witbeck also built (see PB&E, Feb. 21, 2000).

Work on the project began in earnest in July, focusing on infrastructure relocations and modifications. These included three new electrical vaults and six new duct banks for Seattle City Light plus modifications to water services, replacement of conflicting water mains, sewer repairs, and installation of two detention facilities, plus track drain connections to catch basins.

Stacy and Witbeck began using a right of way just north of Valley Street, between Terry Avenue and Fairview Avenue North, as a staging area to store rail and other construction materials.

It wasn't long before the project hit a snag when the effect of a local concrete strike halted work on Seattle City Light duct banks in August. The contractor found it necessary to maintain open excavations with shoring, traffic plates and other devices. At one vault on Stewart Street, it was necessary to temporarily restore the street with materials that would later be removed, because of safety concerns about the long-term use of plates on this major transit route.

"The strike didn't affect us too badly," said John Boknecht, general superintendent for Stacy and Witbeck. "We were able to come up with some alternatives, but we did lose a few days."

Crews shifted from concrete-dependent duct banks to sewer and water work, and the rail installations planned for this period were delayed until the strike was settled.

Rails from Austria

Installation of the streetcar trackways began in September. This work featured excavation of a shallow (18-inch) trench, formwork for reinforcing bars and track placement, and concrete encasement of the track and reinforcement. In selected locations, track drains also were installed, requiring installation of drainage pipes outside of the trackway to connect to existing drainage facilities.

Boknecht went on to say that he actual rails — about 30,000 linear feet — arrived from the manufacturer in Austria in late October and were stored in the laydown area while awaiting installation.

By December, the contractor had achieved substantial completion of over 90 percent of Seattle City Light Downtown Network power distribution infrastructure. The new facilities eliminate conflicts between the Streetcar trackway and existing SCL infrastructure.

As this story is being written in March, the Seattle Streetcar team is performing work related to installing track drain leads in the downtown area, continuing to set traffic signal and catenary pole foundations, and starting pavement restoration along Fairview Avenue.

The contractor expected to achieve substantial completion of Streetcar trackway on Terry Avenue and Harrison Street in March. In addition, work related to Seattle Public Utilities water facilities will conclude at the end of the month.

The Streetcar project also includes construction of a 9,000-square-foot maintenance facility, which is located on Harrison Street between Fairview Avenue North and Minor Avenue North.

The work started in November with the demolition of an existing building, setting temporary shoring and starting excavation of the site. Next, crews drilled and installed piles, set shoring, and excavated the site to track level at the Harrison Street entrance to the maintenance yard.

Site excavation was completed in January, and construction of the foundation for the building began in March.

Coordinating Construction

Motorists in the area have been coping with delays and detours throughout the course of the project.

In fact, coordinating traffic closures and maintaining access for neighboring businesses has been "probably the most difficult aspect of the whole job," Boknecht said.

"You want to take a somewhat linear approach to the job — work from one end to the other," Boknecht explained. "But sometimes that's just not possible."

Adding to the challenge is the large amount of vertical construction taking place in the district concurrent with the streetcar project. These projects add to the congestion as materials and equipment must be delivered on the already-crowded city streets. Stacy and Witbeck holds weekly meetings with vertical contractors working nearby to coordinate their activities so all the projects can keep moving forward, Boknecht added.

The contractor also had to factor for the Holiday moratorium and work around special events in the neighborhood. But considering all the possibilities for problems, the streetcar project hasn't experienced any safety incidents related to traffic.

"We've been very fortunate," Boknecht observed.

Bad weather also has been a factor, first extremely wet weather in November-December followed by cold and snow.

"The real wet month was difficult, but that's part of working in the Northwest," Boknecht said.

Delays caused by the strike and then the weather put a strain on the project schedule, but Boknecht said his team is still on track to finish its work by the September completion date.

Then, after a testing period, the South Lake Union Streetcar will be ready to roll around the end of 2007. King County Metro Transit will operate and maintain the streetcar system for the city.

For more information on the South Lake Union Streetcar project, go to www.seattle.gov/transportation/stcar_slu.htm.

 

Key Project Participants

Owner: city of Seattle Department of Transportation

Designer: Parsons Brinckerhoff

Track Engineering: URS

General Contractor/Construction Manager: Stacy and Witbeck Inc.

Underground Installations: Mid Mountain Contractors Inc.

Street Lighting and Signals: Elcon Corp.

Overhead Catenary System: Mass Electric Construction Co.

Concrete Placement: Leajak Concrete Construction Inc.