ADOT recently completed the new Navajo Bridge, located approximately 150 feet downstream of the historic Navajo Bridge, which remains as a pedestrian crossing. The new bridge is 909 feet long, with a 726-foot-long braced-spandrel, steel-arch main span that carries two lanes of traffic 470 feet above the Colorado River. The new bridge reflects the design of the historic bridge in type, scale, proportion, and materials. The main span arch framing is battered at an 8:1 slope to match the existing bridge. The bottom chord is a 24-inch-wide, 30-inch-deep "H" section that consists of chorded segments of a circular arch with a 90 foot rise at the crown. The top chord consists of 24-inch-square welded box sections, and the web members are perforated welded "I" sections. Bracing members are rolled beam sections. Approach span girders are welded box sections of the same dimension as the top chord to preserve the line of the bridge from abutment to abutment. Piers supporting the approach spans are 16-inch-square welded box columns with rolled beam bracing.
The New Navajo Bridge provides a safe, modern crossing at a reasonable cost and with minimal environmental impacts. It takes its place beside the historic bridge to continue the same vital role in the regions transportation system.
