LEHI — One small step for Utah Transit Authority, one giant leap toward easing transportation congestion along the Wasatch Front.

Monday afternoon, UTA crews showed off their newest mile-long rail addition near the future Lehi station on the FrontRunner South line, which will eventually run from Salt Lake City to Provo.

The 45-mile commuter rail line, which parallels the Union Pacific tracks through the two counties, is slated for completion no later than 2015.

FrontRunner North, which shuttles riders from Salt Lake City to Pleasant View, is already in service.

UTA projects that FrontRunner South will have about 7,500 riders when it opens, but will expand to nearly 13,500 riders per average weekday by 2030 — roughly 330,000 trips each month, said Gerry Carpenter, UTA spokesman.

The south line has proposed stops in Murray, South Jordan, Draper/Bluffdale, Lehi, American Fork, Vineyard, Orem and Provo.

The Lehi station, nestled in the backyard of Thanksgiving Point, has the park-and-ride on the east side of the tracks, with the platform in the middle of the two UTA lines, Carpenter said. The only other station set up that way is in Farmington, where an above-grade bridge was constructed.

Because of that, crews are building an underground pedestrian tunnel to get from a car to the train.

However, that construction can't be done with UP freight trains rumbling overhead.

So, crews created a "shoofly," an old railroad term for a detour, and will move the UP train onto the new UTA shoofly line while they work on the tunnel, Carpenter said.

The nearly mile-long detour track will allow UP trains to keep running during construction in that area, which should be about four months, said Matthew Carter, FrontRunner South project director.

Dan Harbeke, Union Specific director of public affairs, said the railroad is excited about the south line after seeing the success of the north line. And thanks to the shoofly, UP work won't be stalled during the construction process.

Once that section of the tunnel is done, UTA crews will rebuild the UP track over the tunnel and the shoofly will eventually be connected to the rest of the line. The pedestrian tunnel will be finished when crews work on the platform.

"UP has put forth a tremendous effort of coordination with us," Carter said. "We have to have a lot of effort on their side to make something like this happen."

The $850 million bill for FrontRunner South is split by UTA and Utah County, with the county using voter-approved sales tax bonding and UTA using sales tax, fare revenues and other sources, Carpenter said.

Although the original deadline was 2015, Carpenter said work is ahead of schedule and the line could be operating by 2013.

"We are working full-speed ahead on this," he said.

Provo is coordinating with other cities to submit "quiet zone" applications to the Federal Railroad Administration, and Carpenter said he expects all 45 miles of the south line to receive that status, just like the north line.

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