29th Annual Highway Report: Structurally Deficient Bridges

Federal law mandates the uniform inspection of all bridges for structural adequacy at least every two years; bridges rated “deficient” are eligible for federal repair dollars. The National Bridge Inventory (NBI) is the source of the bridge data in the table and figure following, which is provided in summary form in Better Roads (see Appendix). Since the NBI contains some recent inspections and some as old as two years, the age of the “average” inspection is about one year old. So, a “December 2024” summary from the NBI would represent, on average, bridge condition as of December 2023.

The condition of the nation’s highway bridges in 2023 improved slightly from 2022, the last time this assessment was completed. Of the 618,923 highway bridges reported, 42,093 (6.8%) were rated structurally deficient for 2023 (Table 16, Percent Structurally Deficient Bridges, 2023, Figure 11). This represents a 0.10% improvement over 2022 when 6.9% were rated as structurally deficient.

In 2023, Arizona, Nevada, Texas, Delaware, and Georgia reported the lowest percentage of structurally deficient bridges (less than 2%). On the other hand, West Virginia, Iowa, South Dakota, Rhode Island, and Maine have the highest percentage. Compared to 2022, the states whose percentage of deficient bridges increased the most are Utah, South Carolina, Washington, Hawaii, and Vermont (16%, 10%, 8%, 7%, and 6% respectively). The states that improved the most were Delaware (22%), Georgia (18%), Oklahoma (17%), Nevada (14%), and Arizona (12%).