Highway job uses new system

A new interchange serving homes in the Clear Creek Ranch area of U.S. Highway 50 west of Carson City marks the first time the Nevada Department of Transportation used pre-cast arches to form a complete interchange.

Nineteen 35-ton arches were fitted together atop a cast-in-place footing and stem wall to form a tunnel 114 feet wide and 44 feet across.

NDOT Resident Engineer Stephen Lani says aligning the north and south ends of the tunnel was the biggest challenge in the job because the project wasn't built continuously end to end.

NDOT chipped in $1 million for safety and drainage features for the $7.5 million project. Syncon Homes footed the rest of the bill. Prior to starting the job NDOT engineers studied a similar build in the Truckee area. "We got a few pointers, things to look for and be aware of," Lani says.

Other challenges including properly matching the mechanically-stabilized-earth wing walls and the arched panels.

"The miter to get them to mate was a challenge, but it turned out well in the end," Lani says. "We hope to do more of these in the future. It was a sweet little project."

The new interchange required earth cuts to 95 feet deep and leads to Tahoe Golf Club Drive.

The project was designed for Syncon by Washington Group International, which has a satellite office in Las Vegas. The architect was Rod Johnson, and the contractor was Road and Highway Builders.