Bridge Deficiencies

MDOT inspects the condition of the state-maintained bridges while local governments inspect the locally maintained bridges in Mississippi according to the National Bridge Inspection Standards (NBIS). The NBIS provides a uniform set of standards by which to inspect and rate the nation’s structures and includes all bridges with an opening longer than 20 feet measured along the center of the roadway. The materials used in the bridge are considered, as well as the physical condition of the deck, superstructure, and substructure components of bridges and the overall condition of culverts. This information is used to determine condition on a numerical scale that ranges from 0 (failed condition) to 9 (excellent condition).

  • Poor Condition - When the minimum condition rating of any of the four NBI condition ratings for a structure (Deck, Superstructure, Substructure or Culvert) is 4 or below.
  • Fair Condition - When the minimum condition rating of any of the four NBI condition ratings for a structure (Deck, Superstructure, Substructure or Culvert) is either 5 or 6.
  • Good Condition - When the minimum condition rating of any of the four NBI condition ratings for a structure (Deck, Superstructure, Substructure or Culvert) is 7, 8, or 9.