Stuck at the Pecos railroad crossing? Adams County has a $40 million solution for you.

The county plans to start preliminary design for an overpass that would carry Pecos Street up and over the four-track crossing north of 56th Avenue as well as the single-track crossing about 1,000 feet north of there.

The project would eliminate traffic backups that happen when Union Pacific coal trains park across Pecos several times a day. The trains can sit for a half-hour or longer, blocking traffic while waiting for other trains to pass from farther west or east.

But the project could also have consequences for growth on the largely industrial stretch. A grade separation would permit another FasTracks rail transit stop to be located there.

The change in the intersection would help serve new residential growth planned for just to the north.

The county received $10 million in federal grants for the job, and the railroad is willing to put up some money. Other funding is coming over several years from the county's capital improvement program.

"There are many benefits to having a grade separation as proposed by Adams County," said Union Pacific spokesman James Barnes. "We're anxious to move forward with the project and have offered a substantial contribution to complete the project."

When the initial estimate was for $11 million, the railroad offered to pay half, or $5.5 million. But fast-paced inflation in construction costs has pushed it to the new figure and the county will negotiate a new contribution from the railroad.

Only half the funding has been identified, said Jeanne Shreve, county transportation planner. But the county hopes to line up the rest and put the project out for bids sometime next year.

Pecos is a lesser-used north- south corridor than nearby Federal and Sheridan boulevards. Several years ago, it handled about 13,000 vehicles a day. But when Union Pacific built a mainline bypass track around Utah Junction, a busy railroad crossroads just east of the Pecos crossing, rail traffic changed.

Coal trains from out of the mountains often come to a full stop across Pecos. Shreve said that as a result, vehicle traffic on Pecos dropped to about 9,000 cars a day, nearly all of it detouring across 52nd or 56th avenues, Federal or Interstate 76.

"We obviously see a grade-separation project as a solution to that inconvenience," Barnes said.

The county tried to help frustrated drivers by installing automatic warning lights north of I-76 and at 52nd Avenue that flash a detour advisory to drivers when a train is blocking Pecos.

It also paved an asphalt turnaround on property next to the crossing so drivers can pull a U-turn and detour.

A grade separation of Pecos would coincidentally beef up Adams County's chances of getting another FasTracks rail-transit station. Two of RTD's FasTracks corridors - the Gold Line to Arvada and Wheat Ridge and the Northwest Rail to Boulder and Longmont - would use these track rights of way.

Putting Pecos on a bridge over both sets of tracks would allow RTD to build a single station that would serve both corridors. Without a grade separation, only the Gold Line would have a station, just west of Pecos.

Adams County likes the idea of a station that could serve both corridors, because it would allow passengers to transfer more conveniently between Boulder and Arvada.

"What we really like about this is the ability to put a transfer station at Pecos," Shreve said. "You're not only close to I-76 and I-70 but also to I-25 and I-70, so there are a lot of connections that could be made."

flynnk@RockyMountainNews.com or 303-954-5247