Building a road under a freeway? The really hard part is still ahead

Meadow Valley Contractors has begun digging the deep excavation along the east side of Highway 395 that will create a new Meadowood interchange.

But the tricky part comes this fall, when swarms of heavy equipment move to the middle of the highway, where they will work in tight spaces constrained by barriers on both sides of the job.

The $21.8 million project will create an underpass that allows for the extension of Meadowood Drive so that it connects Kietzke Lane and South Virginia Street. Because that section of Highway 395 is elevated, the easier traditional answer building a new overpass wasn't a possibility.

Instead, engineers figured how to build an underpass beneath the highway without disrupting the 90,000 cars that whiz by the site each day.

The knot of machinery now constructing the easternmost portion of the project on northbound Highway 395 will move to the middle phase of the project later this year. When that happens, the Nevada Department of Transportation will re-align lane configurations so that northbound motorists travel on the newly constructed eastern portion of the freeway. Workers and their equipment will move to the middle portion of the freeway.

The final phase of the project, which should be under way roughly a year from now, requires a third lane configuration. Drivers will travel on the two new eastern bridge decks while Meadow Valley Contractors tackles the westernmost section of the job. The project is expected to be completed near the end of August 2012.

Access to the second phase of the project poses a significant logistical challenge for Phoenix-based Meadow Valley, says Cindy Potter of engineering firm CH2M Hill.

Workers must excavate about 20 feet of earth beneath the current roadbed to create the pathway for the Meadowood Drive extension and to correctly position all the heavy machinery to tackle the piers and foundation bore holes. Some of those holes are about 50 feet deep.

Wet days from the snowfall that pounded the region in late 2010 and late February have bogged down heavy machinery and slightly slowed construction on the project as well.

"So far a major challenge has been the weather," says Michele Dennis, project manager for the Regional Transportation Commission. "Traffic has gotten used to the shift, and they will get used to the shift when we are in the middle. But right now the big challenge has been the weather."

The Meadowood interchange is designed to alleviate congestion at the southbound Virginia Street exit by creating an additional off-ramp for southbound motorists. There also will be a new on-ramp for northbound motorists at Meadowood Drive.

Additionally, the project provides a new east-west route for motorists to bypass the South Virginia Street/South McCarran interchange the busiest interchange in northern Nevada, says Scott Magruder, NDOT spokesman.

NDOT estimates that on a daily basis more than 40,000 cars use South Virginia Street to cross South McCarran, and more than 26,000 cars use South McCarran to cross Virginia Street.

"We expect to see a relief in congestion and hope motorists will use Meadowood Drive to get to Kietzke and thus avoid the busy South Virginia/South McCarran intersection," McGruder says.

The project was entirely funded under Washoe County's allotment of federal funds distributed through the American Recovery and Reinvestment Act. The RTC will update owners and managers of businesses in the area of the construction from 5-6 p.m. May 17 at the Meadowood Courtyard.