Project Description


As part of the Arizona Approach to the historic Hoover Dam Bypass Project, Jacobs Engineering was responsible for the roadway and bridge design and Vastco entered into a joint venture with R.E. Monks to complete the construction of this $24 million project. Jacobs worked with CFLHD and the BOR to provide an efficient alignment that accented the approach of the historic dam.

As construction manager for the approach project, Vastco coordinated the effort to construct two new structures that cross a 160-foot deep desert canyon and approach the Colorado River approximately 1,500 feet downriver from Hoover Dam. The signature Sugarloaf Mtn. structure is a 7-span 902-foot long concrete type 6 AASHTO girder bridge crossing a ravine used by Bighorn Sheep. The other structure is a single span 145-foot long type 6 AASHTO girder bridge that will become the traffic interchange accessing to the Hoover Dam and BOR recreation lands.

Performed in an environmentally sensitive habitat, the project team drilled, shot and excavated 1.7 million cubic yards of materials, constructed bridges, realigned the existing Hoover Dam access roads, and improved Park Service access. Construction limits were tightly maintained. All work minimized impact to endangered Desert Bighorn Sheep and Desert Tortoise. The Monks-Vastco joint venture team of experts completed the $21.5 million Arizona Approach on time and within Federal Highway Administration schedule.

“Thank you again for Vastco’s expeditious support and recent completion on the Bureau of Reclamation’s Visitor Center Bridge. Successful completion of this urgent project required innovative solutions, integration of technical recommendations, and joint valuation of alternatives. A true team effort.”
F. Dave Zanetell, P.E., Hoover Dam Bypass Manager FHWA