Commuter trains won't be rolling to Salt Lake City or Utah County after Union Pacific rejects the county's plans.

There was a hope that trains full of passengers would soon be sharing rail tracks with freight trains, but Union Pacific says until Utah County has a plan to pay for dedicated commuter rail lines in the future they aren't going to share in the short term.

"They wanted to make sure Utah County had the ability to pay for a permanent solution for commuter rail before they allowed us to use their tracks temporarily. They don't want to be stuck with it," says Mountainland Association of Governments Transportation Planner Chad Eccles.

Eccles also says the move was expected. Officials say even if the county adds a quarter-cent sales tax, they'll still need to raise more money for the project. They say, though, that finding new transportation options is critical before I-15 in Utah County is rebuilt in about five years.