The Utah Department of Transportation's (UDOT) $133 million, two-phase Interstate 15 Springville to Spanish Fork Interchange project will see phase 1 completed shortly, with a second phase set to start at the same time.

Sunroc Construction & Materials secured the contract for the first phase ($16.4 million), and Wadsworth Brothers Construction will construct the second phase, which is expected to finish in the summer of 2026. The project is financed by state and federal funds.

The project is constructing a new I-15 Interchange at 1600 S /2700 N and widening the road from Main Street in Spanish Fork to the Union Pacific Railroad (UPRR) Tintic Line in Springville, as well as installing a shared-use path on the north side of the widened road, building a bridge over the UPRR Sharp Line, erecting a noise wall and completing utility relocations east of the UPRR Tintic Line.

UDOT also will rename 1600 S 2700 N to Dry Creek Parkway to create continuity through the cities.

"North of the new interchange is the interchange at 400 South and Springville, which gets a lot of traffic from the cities of Springville and Mapleton," said Tryrell Edwards, district engineer for UDOT District 3. "There is no interchange that serves Mapleton very well. The interchange we are building provides more access to I-15, takes pressure off the existing one and connects I-15 to State Route 51."

Planning for the project began in 2017.

"The new interchange will be close to the U.S. 6 interchange and, in order to make this juncture work, we went through our interchange access request with the Federal Highway Administration and worked with them to develop a three-quarters interchange," Edwards said. "We have northbound on and off ramps and, southbound, an off-ramp. Traffic that needs to exit southbound will use the U.S. 6 interchange."

Phase 1 work included the earthwork for the northbound and southbound on-ramps, which eliminated some local frontage roads, utility relocations and the relocation of some of the frontage roads.

Phase 2 includes the widening of 1600 South (Drake Creek Parkway), the construction of the bridge over Union Pacific tracks and associated elements.

"This was the first digital delivery roadway project in our region," said Edwards. "It's been done in other areas, but it's different for our inspectors and contractors. Wadsworth has had some experience with digital delivery. It's kind of a big shift — just the fact that it can create some complications and unforeseen consequences where you have work done by another contractor and then up by another contractor that does not see the project as phased.

"This project was phased to get work going while right-of-way purchases were being made and utility issues had to be worked through. We were trying to accelerate the schedule. We're aware that it kind of forces contractors to be flexible."

Austin Davies, Wadsworth's engineering project superintendent, noted that one of the challenges is the many settlement areas, groundwater and railroad lines.

"This includes the railway design and getting enough height while maintaining low profiles," he said. "Moving all the power infrastructure was a concern as the area is a big hub for the power lines."

Wadsworth is using cellular concrete to replace the lightweight fill that the contract originally required.

"Wadsworth approached us, saying there is less risk if we use cellular concrete," Edwards said.

Davies appreciates the help provided by UDOT.

"UDOT's team has been great all the way from their district engineer down to the chief building inspector," he said. "They've been really good to work with. It's a good, collaborative effort, and we solve a lot of problems that come up."

Sunroc Construction constructed the new frontage roads, from earthwork to paving, on a greenfield site. The contractor also excavated the ground and built the ramps and the tie-ins.

The asphalt-lane roadwork had excavation, site prep and paving crews operating simultaneously at one point.

"They had the same challenges that Wadsworth has — poor soil conditions and high groundwater," Edward said. "Sunroc worked well with us. It was a bit of a challenge for them, just coming into DOT work and a digital delivery project. Before this, they worked on city projects. They worked well and were good to partner with."

Phase 2 work is progressing well.

"Our schedule is driven by the settlement periods in our work zone, which can be up to three or four months," Davies said. "We're attacking that with mass fills."

Sunroc's earthwork operations generated approximately 500,000 cu. yds. of fill.

"We're trying to get the clock going to get the settlement periods done with so when we construct our bridge, we're ready to go," Davies said.

Wadsworth has an earthwork crew handling the mass fills, two to three crews on drainage and storm drains and various crews moving power lines.

"Our plan of attack is to get the fills placed, build our MSE walls and get them ready for the bridge," Davies said. "We're hoping for a late summer start for the steel girder bridge construction, which will improve that crossing over the tracks. Currently, there are pretty big delays as the tracks are connected to a train depot."

To construct the bridge, piles will be driven and filled, followed by installing walls, the pouring of reinforced footings at the tops and then the placing of the steel girders. Following these operations, a partial precast concrete deck panel system will be placed to span the gap between the girders, followed by the rebar and the deck pouring.

The deck panels are approximately 3.5 in. thick, and the deck will be approximately 5 in. thick.

Working at such heights requires a rigorous safety program.

"The beams and girders are up in the air," said Davies, "so we had our manufacturer weld in some anchor points and bolts. We have a safety line system so that everyone can be on lanyards and tied up above the tracks. We have a bunch of safety plans that we go through should someone fall and ensure that everyone respects the plans."

The 134,000-lb. steel beams will be lifted by and placed into position by a Kobelco 2500-2 250-ton crawler crane.

The project will use 1.1 million tons of steel, including the steel girders and rebar.

The Kenny Seng Co., the subcontractor responsible for the earthwork, is using CAT D8 dozers, smaller skid steers, rollers and track hoes. They built 1.2 mi. of road, with two lanes in each direction and a shoulder on each side.

For the bridge work, Wadsworth also is using 50-ton mobile rough-terrain cranes and 12,000 lb. capacity forklifts, track hoes and smaller equipment. CEG