OREM — In the race to build roads and rails in Utah County, Utah Transit Authority's FrontRunner Commuter Rail project is ready to roll past plans to expand Interstate 15.

Utah's Department of Transportation is coming to the end of a three-year environmental study that's been examining widening I-15 from Sandy to Payson, but a lack of funds has placed the project behind the schedule of commuter rail's completion in Utah County.

UDOT is planning several public meetings in the next two weeks to update residents and commuters on the project's progress.

"We're assuming we're going to build this (I-15 expansion) starting in 2011 or 2012, but if the funding stream doesn't develop, then we won't," said Merrill Jolley, I-15 project manager for UDOT. "This is probably the biggest and most expensive project UDOT has undertaken."

Jolley didn't give an estimate of much the project will cost — that's still to be determined — but he compared the project to a 17-mile, $1.5 billion makeover that UDOT completed on I-15 in 2001.

"This project is three times as long, and costs have only gone up," Jolley said.

The I-15 expansion includes adding two lanes in each direction from Bangerter Highway to Benjamin, and one lane in each direction from Benjamin to south Payson. Two new interchanges — one in north Lehi and one at 800 South in Orem — are being considered, as well as the reconstruction of several existing interchanges.

The expansion and new interchanges are expected to have some impact on wetlands and homes in the area, but UDOT has not yet determined the full scope of that impact. Jolley says gathering that information is part of the environmental study process.

UTA is also working to study the impact a new commuter rail system in Utah County will have.

The passenger train is planned to operate on new tracks that will be built by UTA next to existing Union Pacific lines in order to give more flexibility and frequency to the system.

"We are competing with the higher speeds of car travel, so we are looking for higher speeds and travel times" said Steve Meyer, UTA project manager over commuter rail.

Coming from the Salt Lake City intermodal center, which is currently under construction, Meyer said FrontRunner would stop infrequently on its way to Provo.

The train is expected to stop at 5300 South in Murray; 103000 South in Sandy; Bangerter Highway in Draper; Thanksgiving Point in Lehi; Main Street in American Fork or in Pleasant Grove; Vineyard; University Parkway in Orem; and University Avenue in Provo. In future phases, it is expected the rail would continue to Payson.

UTA estimates the cost to build commuter rail from Salt Lake City to Provo will be $875 million, and the cost from Salt Lake City to Pleasant View will be $541 million.