Deficient Bridges — 23rd Annual Highway Report

Percent of Bridges in Deficient Condition
2017 Annual Highway Report

Federal law mandates the uniform inspection of all bridges for structural and functional 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 below, although we use summaries provided 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 2016” summary from the NBI would represent, on average, bridge condition as of 2015.

The condition of the nation’s highway bridges in 2015 worsened slightly from 2013, the last time this assessment was completed. Of the 603,366 highway bridges reported, 130,623 (about 21.65%) were rated deficient for 2015 (Table 15, Percent of Bridges in Deficient Condition, 2015, Figure 6). This represents a 5.9% worsening over 2013 when 124,265 of 607,885 (20.44%) were rated as deficient.

Arizona reported the lowest percentage of total deficient (functionally obsolete and structurally deficient) bridges, 9.01%, while Rhode Island reported the highest, 52.01%. Over half the states (26) reported at least some improvement in the percentage of deficient bridges from 2013 to 2015, with Pennsylvania and Wyoming seeing the most improvement (3.4 and 2.7 percentage points, respectively). One state reported essentially no change. Of the 23 states that reported a higher percentage of deficient bridges, nine saw increases of more than two percentage points. Two of these nine, California and Ohio, did not include functionally obsolete bridges in their deficient bridge totals for 2013. As a result, these two states saw double-digit increases, but returned to their historical averages. One other state, Nevada, also saw a double-digit increase in deficient bridges of 10.9 percentage points.

Percent of Bridges in Deficient Condition