The head of Mississippi's transportation department says replacing local bridges is the most critical transportation need in the state.
Larry "Butch" Brown says many county road bridges were built when trucks were much smaller, and are carrying more than they were built for.
John Harper, an assistant administrator in the Office of State Aid Road Construction, says Mississippi has almost 11,000 local bridges -- not part of the interstate or state highway systems.
He says nearly one in four is rated 50 or lower on a 100-point scale -- indicating they need repair, replacement or a reduced load limit. He says that if replacements average $250,000, replacing them all would cost nearly $666 million.