Premier was retained by the City of Phoenix to prepare a design concept report and environmental determination report for this highly visible and complex project in the most prestigious business neighborhood in Phoenix. After preliminary evaluation of alternatives, the underpass option with an aesthetically enhanced plaza at each entrance was recommended. The City then requested that Premier complete the final design of the recommended alternative.
The entire roadway segment from 24th to 26th Streets was geometrically revised to design the underpass as a shallow crossing. The vertical profile of Camelback Road was raised by about six feet at the underpass location and matched to the existing grades just east and west of the 24th and 26th Street intersections, respectively. The horizontal alignment of the roadway was significantly changed to create an additional plaza area on the south side of Camelback Road.
The complex structural design incorporated unique architectural and aesthetic features. Drainage design included analyzing off-site contributing runoff using HEC-1 and storm drain reconstruction to lower the existing storm drain to pass under the new pedestrian underpass. Utility relocation (including fiber optic duct banks) and construction sequencing in one of the busiest sections of Phoenix made the underpass design very challenging. Due to the complexity of the project, Premier conducted numerous design workshops and public meetings.
The Camelback Road Pedestrian Underpass Project won 10 local and national awards.