A pedestrian walkway over I-15 to serve the county's new jail and court complex in west Farmington may cost around $250,000 to build, the Davis County commissioners were told this week.

The walkway adjacent to the State Street overpass is one of the stipulations Farmington officials added to the project before giving it final approval.County Public Works Director Sid Smith asked the commission Wednesday for a $6,000 appropriation for its portion of the $60,000 needed to do an engineering study for the structure. The commission approved the request.

The remainder of the funds for the engineering study and most of the actual construction work will come from federal secondary highway funding, Smith said.

The walkway will be eight feet wide and nearly 400 feet long to span the freeway. It will be adjacent to but not attached to the existing overpass, Smith said.

The county at first wanted to replace the two-lane overpass with a wider one to handle more traffic and a pedestrian walkway, Smith said, but those plans proved unworkable.

The freestanding walkway has to be designed to meet federal capacity and load-bearing standards equal to that of a highway bridge, Smith said. The county is now pushing to have it built as a covered, rather than open, structure to mitigate snow removal problems.

Smith said the Utah Department of Transportation is resisting that portion of the proposal because of problems it has with children climbing up on top of the roof of similar walkways, creating a potential safety and liability hazard.

But Smith said he believes a covered walkway can be designed to prevent that. And the benefits of a covered walkway over an open one, especially in winter, are obvious, Smith said.

Snow would have to be removed from an open walkway, he said, but it would have to be hauled off the structure rather than just dumped over the side, onto the freeway.

"You might have to empty the jail of inmates for a couple of hours every time it snows, with them hauling the snow off of it in buckets," Smith said. "That's about the most feasible way of clearing it that I can see."

The environmental impact statement for the walkway has already been done, Smith said, with the engineering design the next step. If the design is finished and approved in good time, the walkway will be built this summer and completed by fall, he said, adding that prediction could be optimistic.