Over the past decade, there has been increased awareness of the significance of bridges to our nation’s economy and the safety of the traveling public. At all levels of government, a concerted effort has been made to reduce the number of structurally deficient bridges in the U.S.—bridges that require significant maintenance, rehabilitation, or replacement. Structurally deficient bridges are not unsafe, but could become so and need to be closed without substantial improvements.
As of 2016, one in 11 (9.1%) of bridges were designated structurally deficient, which represents an improvement from a decade ago when 12.3% of bridges were structurally deficient. As bridges greatly vary in size, the percentage of deck area that belongs to structurally deficient bridges is another useful indicator. 6.3% of total bridge area belonged to structurally deficient bridges in 2016, an improvement from 9.5% in 2007. Encouragingly, higher traffic volume bridges are less likely to be structurally deficient. Yet, on average, there were 188 million trips across a structurally deficient bridge each day in 2016. Some states are doing better than others at maintaining, repairing, or replacing their bridges. The percentage of bridges that are structurally deficient ranged from 1.6% in Nevada to 24.9% in Rhode Island in 2016.