CEDAR CITY — Those traveling southbound on Interstate 15 Wednesday night had to take a short detour through Cedar City while the Utah Department of Transportation slid a 1.1 million pound bridge into place using a hydraulics system and a bit of Dawn dish soap.

Work on the bridge replacement project over East Nichols Canyon Road began last July, according to a press release issued by UDOT. I-15 was closed from Exit 62 to Exit 59 at 9 p.m. Wednesday while crews completed the final leg of the project. The interstate reopened at approximately 6 a.m. Thursday morning.

Last year, UDOT built a center bridge between the north and southbound freeways. Northbound traffic was diverted to the center bridge as the northbound bridge was demolished and rebuilt, according to the release.

After which, southbound traffic was shifted to the center while crews demolished the existing bridge and rebuilt the support structure that would hold the new bridge deck, resident engineer Tyrell Wood said.

“So, that center bridge will no longer exist, so to speak,” he said.

By designing the project this way, UDOT was able to reduce traffic interruptions to approximately nine hours, despite construction lasting more than a year, Wood said.

Wearing hard hats and high-visibility vests, crews generously applied dish soap to Teflon pads to keep “everything slippery and moving,” Wood said. As part of the hydraulics system, long “screws” rotated, causing the bridge to inch toward its final location. The slab was only allowed to move several inches at a time, which varied as crews worked to ensure that spacing on each side was approximately equal.

“Dawn dish soap is the secret ingredient,” he said.

The project lasted 394 workdays and took an estimated 39,176 man-hours to complete, according to a fact sheet sent to Cedar City News by Lisa Hunt Beck, Harmony Public Involvement’s president and senior project manager.

However, Wood said that sliding the bridge into place was the “easy part,” adding that upon completion, crews had to paint the white and yellow lines, hook up the guardrail and move the concrete barrier.

“There’s quite a bit of work that people really aren’t going to see and care about,” he said.

At the end of the process, there was, at most, a 3/100 inch difference between each corner of the structure, said Beck, adding that a difference of just 3/4 inch would have been considered a failure.

Wood said that not only were backup plans put into place, but the engineers had “contingency plans for contingencies.” Additionally, the bridge slid into position quicker than he anticipated.

“This has been a very smooth bridge slide,” he said.

The bridge project was planned after an analysis by UDOT to determine what was needed across Utah. Wood said the organization found that the project was warranted as the old bridges were wearing out.

UDOT transportation commissioner Donna Law said that the effort was funded three years ago, and that watching the idea evolve, get prioritized, funded and now realized was rewarding.

“UDOT has teams of people all across the state, who are coordinating with communities to prioritize what’s important not only for the state as a whole … but to also help communities improve their transportation systems,” she said.

Wood said building a new bridge ensures a “longer life of the road.” Additionally, the bridge was constructed to allow for future expansion if the need for additional lanes or another bridge arises, which he said saved taxpayers money.

Councilmembers Teri Hartely and R. Scott Phillips, and several students and professors from Southern Utah University’s Engineering and Construction Management program attended the event to observe the slide. Phillips said the project was “very exciting and very beneficial for Cedar City.”

SUU freshman Justin Ndjondo said that it was “amazing” to see the bridge moving and that he was excited for the future of engineering.

“And I’m definitely motivated,” he said.

Additionally, UDOT plans to lower East Nichols Canyon Road, which runs beneath the bridge, said Wood, adding that nearby utilities have already been lowered. Most of the work was completed before the bridge slide event, and the road is expected to open mid-August.

The project will be fully completed by mid-September, the release stated.

To learn about UDOT’s ongoing projects, visit their website here and watch UDOT’s time-lapse video of the bridge slide below:

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