I-15 South Gets Critical $252.5 Million Tune-Up

Southern Nevada's busiest thoroughfare, Interstate 15, is getting a makeover.  

The stretch of roadway sees more than 200,000 vehicles a day, and is plagued by gridlock and accidents. Design-build contractor Las Vegas Paving Corp. began work in late 2009 on a solution: a $246.5-million widening of I-15 South between Silverado Ranch Boulevard and Tropicana Avenue. Jacobs Engineering Group Inc., Pasadena, Calif., performed design.

The project is being underwritten by the Las Vegas Convention Visitors Authority, the public-private entity charged with bringing more visitors to town through hotel room tax-backed bonds. “Southern California represents about 25% of all our business, so we have to make sure they can get here,” LVCVA President Rossi Ralenkotter says. “Transportation is the key to bringing business to Las Vegas.”

The project will upgrade a 7-mile-long stretch of interstate, with 35 lane miles of new asphalt and concrete roadway, plus three new bridges and three interchange reconfigurations. Other improvements call for 35 retaining walls, storm drainage and 1.5 miles of sound walls, as well as landscaping and an intelligent messaging system.

As big as the job is, it has gotten bigger since breaking ground in March 2010. The Nevada Dept. of Transportation added express travel lanes between the 215 interchange and Silverado Ranch Road, and redesign work was needed due to private right-a-way property that feel fell into foreclosure. The project price-tag has grown by $6-million, as a result.

“Once this project is complete, it will greatly improve traffic congestion while increasing safety,” says NDOT Director Susan Martinovich. “All the improvements, especially a better merge on and off, will be greatly appreciated by the local and regional users.”

The multifaceted undertaking requires up to 300 craftspeople, 95 designers and 3,500 pages of plan documents. The contract carries up to $560,000 in bonuses for early completion, as well as $10,000-a-day in potential late penalties. Construction is scheduled to finish in full by mid-2012, as planned, although project components are becoming operational piecemeal upon completion.

The $22.6-million Sunset Road Bridge, for example, made its debut January 13. The 550-ft-long by 60-ft-wide flyover carries east-west traffic over I-15 between Valley View and Las Vegas boulevards. The four-span steel girder bridge has four travel and two turning lanes, with 29,500-sq-ft of precast abutment walls. The project will add 26 bridge segments in total, including a reconstructed Warm Springs flyover to the south and a widened Union Pacific Railroad overpass to the north.

The 120-ft-long, 60-ft-wide railroad bridge is being expanded from two to four spans, with work occurring over a couple of marathon weekends in order to minimize traffic disruption. (The project requires 12 paved detour roads). The two-lane Russell Road flyover, meanwhile, is being demolished and rebuilt as a 360-ft-long, 100-ft-wide bridge carrying six lanes of traffic over two spans that ups its capacity.

A trio of interchanges will soon have added capacity, too, thanks to a combination of wider roads and new collector-distribution lanes that eliminate merge and weave traffic. Blue Diamond Road, for instance, gets a new 900-ft-long by 40-ft-wide direct connection flyover from eastbound Blue Diamond to northbound I-15, while the 215 Beltway interchange is undergoing median and bridge widening, and getting a new ramp from 215 westbound to new collector-distributor roads.

Las Vegas Paving is taking a divide-and-conquer construction approach by splitting the job into four major zones, with work taking place as plans were still being drawn. The contractor is performing 75% of the work itself, which, the company says, gives it better control over schedule, quality and safety. Las Vegas Paving would know. The contractor successfully completed the state’s first design-build project in January 2010 – a $242-million widening of I-15 north that finished under budget and nine months early.

“That project was a great learning process, says Corey Newcome, Las Vegas Paving division manager. “I doubt we would be doing this job, if we hadn’t done that other one.”

The current undertaking requires up to 300 craftspeople, 95 designers and 3,500 pages of plan documents. The contract carries up to $500,000 in bonuses for early completion and $10,000 a day in potential late penalties, Newcome says.

Completion is scheduled for mid-2012, although components are being opened as they are finished. The $22.6-million Sunset Road Bridge made its debut on Jan. 13. The 550-ft-long by 60-ft-wide, four-span steel girder bridge has four travel and two turning lanes, with 29,500 sq ft of precast abutment walls.

“The widening will add 30% to 85% more capacity to the project corridor, depending on the segment,” says Steve Hagel, Jacobs' deputy program manager. “Braiding of the successive on and off ramps will eliminate the severe weaving problems, which in turn will have a significant positive impact on traffic flow and safety.”