Utility and rail infrastructure for Tucson’s Sun Link is complete and light rail service will begin in July — the first such service since the Old Pueblo Trolley was suspended when Sun Link began construction in 2011.

The project, also known as the Tucson Modern Streetcar, overcame  challenges including tie-overs for water lines, two large Fourth Avenue street festivals, and the presence of historic civil infrastructure, according to members of the project team.

“Normally, our approach is to locate all of the obstructions along a utility route, and then dig like crazy in between them,” said Sun Link Construction Superintendent Stanton Jernigan of Granite Construction. “On this job, our operators were very delicate and cautious all the time because we encountered so many unmarked utilities.”

Its projected overall cost of $196 million is being met through a combination of local funding sources and federal grants.

Sun Link is comprised of 3.9 miles of fixed rail connecting the Arizona Health Sciences Center, University of Arizona, University Main Gate Square, Fourth Avenue Shopping District, Tucson Convention Center and the downtown district, and Mercado District development zone currently under development west of Interstate 10.

Components

The $8 million Sun Link Operations and Maintenance Facility is on the transit route at the intersection of Fifth Avenue and Eighth Street. Its construction took place from May 2012 to August 2013.

The developers also extended the 320-foot Luis G. Gutierrez Bridge from the I-10 frontage road to Avenida Del Convento in 2012. It opened to bicycle and pedestrian traffic in fall 2012, and will take streetcar, automobile, pedestrian, and bicycle traffic across the Santa Cruz River on Cushing Street.

A $56 million contract for removal of existing roadway, installation of track, resurfacing, utility relocation, and construction of the system’s 21 stops was awarded to Old Pueblo Trackworks. Phase 1 built straight sections east of the Congress and Granada stop, and the work required rolling closures of Congress Street, Broadway Boulevard, University Boulevard, Fourth Avenue, Second Street, Helen Street, and the Warren Avenue Underpass. Phase 2 includes all work west of the Convention Center, continued work on Broadway and the Warren underpass, and corner sections requiring fabrication of curved track elements.

Sun Link will maintain a fleet of eight United Streetcar model 200s. Tucson placed an initial $26 million order for seven cars in June 2010, and the eighth gar was ordered for an additional $3.6 million in July 2012 to satisfy Federal Transportation Administration requirements for an additional spare.

The United Streetcar 200 is a 66-foot long, bi-directional electric rail vehicle with three sections. The center section floor is at platform height with two double-door entrances on each side. Propulsion is provided by four 90-kW motors drawing power from the overhead line. They have a maximum speed of 70 km/h and a total passenger capacity of 156. The model 200 is nearly identical to the model 100, which was built for the Portland Streetcar system; the only difference is that the 200 is equipped with an upgraded air conditioning. The design of the model 100 is based on the Czech-made Škoda 10 T car.