Metro reached a construction milestone with its new transit maintenance facility Wednesday, inching closer to getting the $34 million project under roof.

Ironworkers with Industrial Steel Erectors, Davenport, hoisted the fourth of five 80,000-pound trusses atop the Rock Island structure. The

130-foot-long truss spanned what was called “the heart and soul” of the building — the actual maintenance area.

Jennifer Garrity, Metro’s administration manager, said the maintenance area “is why we’re doing this building in the first place.”

Located at 4501 4th Ave., next to the Quad-City Industrial Center, the 150,000-square-feet transit maintenance facility will be double the size of Metro’s existing facility, also in Rock Island. In addition to providing area for bus maintenance, the new building will include an area to store Metro’s fleet, a service area, offices for operations and administration and a bus wash.

Rob Knight, project manager for Weitz, the construction management team, explained how the trusses were lifted in tandem by a 40-ton crane from Industrial Steel Erectors and a 300-ton crane from Cattani & Son Inc. The trusses were assembled on site by Vegter Steel Fabrication of Morrison, Ill.

“The big crane is a blind lift,” he said, explaining that the operator’s view was blocked by one of the building’s concrete walls. “That is something you don’t see every day.”

The latest work paves the way for the roof deck to be completed, Knight said. He added with the roof and pre-cast concrete walls, the interior mechanical, electrical and plumbing work will be able to begin in March.

Dan Payne, Metro’s project manager, said the new building’s design will improve the efficiency of the maintenance operation. “In the current facility, there are four main bays. You have to back a bus out to bring another bus in,” he said.

Additionally, he said the design allows for a future expansion to the east. The facility will hold Metro’s existing fleet of about 70 buses —

70 percent of which run on compressed natural gas — as well as the Channel Cat boats in the off-season.

“We’re so excited for the city of Rock Island and the east side of Rock Island,” said Joy Murphy, Rock Island’s 6th Ward alderman, who lives near the Metro project. “We think this is the beginning of a lot of development along the corridor. We’re thrilled.”

According to Garrity, about $28.6 million of the $30 million allocated to the actual construction has been contracted to local contractors and suppliers. The general contractor is Bush Construction, Davenport.

She added that the project is aiming for Leadership in Energy & Environmental Design, or LEED, Silver Certification. LEED is a certification process that measures sustainability that was developed by the U.S. Green Building Council.

About 200 workers are expected to be on site at the peak of construction, Knight said, estimating a total of 225,000 labor hours will be put into the project. It is expected to be completed by February 2014.