U.S. 90 Bridge Over Biloxi Bay
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, Mississippi—was one of many major highway and railroad bridges knocked out of service due to extensive storm damage.
The eye of the storm passed 60 miles west of Biloxi. Peak wind gusts of up to 100 miles per hour, a peak storm surge height of 22 feet, and waves of up to 8 feet roared through the bay. 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 (FHWA) elected to replace it with a new high-level bridge using the design-build project delivery method, which allows design, engineering, permitting, and construction activities to be conducted simultaneously. A relatively new concept for MDOT, the design-build project delivery method is essential for a fast-track project.
MDOT awarded the contract to rebuild the bridge to GC Constructors (GCC) and its subcontractor, Parsons. A critical factor in MDOT’s selection of GCC was the team’s technical score: GCC received the highest technical score on the proposal.