Cracks discovered in both spans of the elevated parts of U.S. Highway 90 over and near Bayou Ramos have resulted in detoured truck traffic and will likely result in repair work later in the summer.

The causes of the cracking to the bridges, built in 1994, are still under investigation by the state Department of Transportation and Development.

“While conducting a routine inspection in March, DOTD bridge inspectors noticed cracks on the twin spans of the Bayou Ramos Bridge located on U.S. 90 in St. Mary Parish,” Deidra Lockhart of the DOTD said.

“Currently, DOTD has reduced load limits and detoured truck traffic weighing greater than 15-25 tons to guarantee that no further damage will occur to the structure until the cause of such damage is known,” she said. “The bridges continue to remain safe for vehicular traffic.”

Phase I of a rehabilitation project to begin repairs to the bridge is scheduled to begin in August 2012, Lockhart said, with construction commencing within 60 days after the bid date.

“The weight restrictions may be lifted after some of the initial work and testing is done this summer. The estimated cost for Phase I is $2.5 to $5 million,” Lockhart said.

Work on girders deemed high-priority — those with visible cracks — will be addressed in Phase I. Remaining girders will be addressed in Phase II, which is scheduled to take place in fiscal year 2013-14 at an estimated cost of $15 to $20 million. There is no estimated timeline for completion of the project, she said.

Truck traffic is detouring on La. 182 and Lake Palourde Bypass Road.

A DOTD engineer said earlier this week that the Bayou Ramos twin spans are the worst road problem in Louisiana. They were completed during the administration of Gov. Mike Foster of Franklin, who pushed DOTD officials to complete the roadway as quickly as possible.