The US 90 Bridge Replacement project includes the design of a replacement bridge over the Perdido River on a slightly shifted alignment to the south to allow construction to take place in a single phase with minimal impacts to the motorists. The bridge consists of seven 106 foot spans using AASHTO Type IV Beams supporting a cast-in-place composite concrete bridge deck. Due to the very high-scour potential, in excess of 20 foot at some locations, the intermediate bents required special designs with pile lengths in excess of 140 foot. Project includes an alternatives analysis to determine the most appropriate alignment option, preparation of a Bridge Hydraulic Report, Bridge Development Report, approach roadway plans and environmental and permitting for a new two-lane facility on a hurricane evacuation route over the Perdido River, which is classified as an Outstanding Florida Waterway.
