Design, construction support
Hurricane Katrina, one of the deadliest and costliest natural disasters in U.S. history, made landfall on August 29, 2005, devastating the Gulf Coast. The U.S. 90 Bridge over Biloxi Bay — connecting the communities of Biloxi and Ocean Springs, MS — was one of many major highway and railroad bridges knocked out of service due to extensive storm damage. Overall, spans that had a soffit elevation of 23 feet or less were badly damaged, and many of the low-level superstructure units were thrown off of the pile caps and into the water — some of the units were even flipped upside down.
The original bridge consisted of low-level approach spans with a bascule navigation span. The Mississippi Department of Transportation (MDOT) and the Federal Highway Administration elected to replace it with a new high-level bridge using the design-build project delivery method. MDOT awarded the contract to rebuild the bridge to GC Constructors (GCC) and its subcontractor, Parsons.
As Lead Design Engineer, we were responsible for the design and construction support for the bay bridges, CSX Railroad bridges, and approach roadways. The new bridge consists of dual structures, each carrying three lanes of traffic. The eastbound bridge also has a 12-foot shared use path. The total width is 129 feet. The bridge was also designed to withstand hurricane-force winds and waves similar to those of Katrina. Aesthetics were an important consideration in the design development.
The first bridge was opened to one lane of traffic in each direction 2 weeks ahead of schedule, and the entire project was completed 1½ months ahead of schedule. In addition, the Parsons-led design team completed 90% of the design work within just 6 months. The use of precast construction and the development of an assembly-line production approach for both design and construction work combined to deliver this emergency reconstruction project in record time and with a high degree of quality.
The opening of the bridge marked a milestone in the Gulf Coast’s recovery from Hurricane Katrina. Our efforts on this project restored a critical connection between the communities of Biloxi and Ocean Springs, reviving the economic vitality of the Mississippi Gulf Coast and helping its residents get their lives back to normal. We performed our work ahead of schedule and developed a design that supported the contractor in delivering the project on budget. This success demonstrated Parsons’ ability to deliver complex technical and management solutions while providing value to its clients and service to the community.
Featured Oct 2008/Updated Jul 2017