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Interstate 11, Boulder City Bypass: Constructing a Critical Link between Las Vegas and Phoenix

A portion of the project is being constructed through a ridge of the El Dorado Mountains. Photo courtesy of OlsenBeal.

Las Vegas, Nevada, and Phoenix, Arizona, are the only two cities in the United States with populations greater than one million that are not currently linked by an interstate highway. To enhance travel and commerce in the region, the Nevada Department of Transportation (NDOT) and the Regional Transportation Commission of Southern Nevada (RTC) have been working concurrently to build the Nevada portion of the new interstate highway, which will eventually connect the two cities.

The proposed new Boulder City bypass, Interstate 11 (I-11), is being built in two major phases from the Las Vegas Valley to the Nevada/Arizona border. The Phase 1 project is being led by NDOT and will construct a 2.5-mile-long, four-lane roadway from Railroad Pass to U.S. 95. Simultaneously, the Phase 2 project, led by the RTC, will complete I-11 from U.S. 95 to U.S. 93 near the Hoover Dam bypass bridge and will include approximately 12.5 miles of new four-lane interstate freeway with a new interchange at U.S. 95 and a reconfigured interchange at the U.S. 93/State Route 172 Hoover Dam exit. Phase 2 is being constructed under a design-build contract, which includes more than 6 million cubic yards of rock excavation through the Eldorado Mountains, 10 bridges, over 100 culverts, a wildlife overcrossing, and a scenic overlook more than 1,000 feet above Lake Mead. A portion of the project is being constructed through the Lake Mead National Recreation Area under the jurisdiction of the U.S. National Park Service. Current traffic between the two states averages about 34,000 vehicles per day, and the new interstate will accommodate future travel demand and improve safety and mobility for motorists, while relieving congestion for Boulder City residents.

As a subconsultant to Louis Berger, BergerABAM helped provide comprehensive project development and design management services for the Phase 2, $300 million design-build project. In the earlier stages of the project, services included toll analysis, value engineering, preparation of the public/private partnership model, and presentations to the state legislature. Later stages of the project consisted of preparing the preliminary design (30 percent), request for proposal documents, and performance specifications of the four-lane freeway. After the RTC awarded the construction contract to a design-build contractor, Louis Berger and BergerABAM managed the contractor’s design compliance with the project specifications and NDOT standards.