46,000 US Bridges Are Structurally Deficient with No Repair Timeline

The American Society of Civil Engineers reports that 46,154 bridges in the United States are classified as structurally deficient, meaning key structural elements are in poor or worse condition. That is roughly 7.5% of the nation's 617,000 bridges. Americans cross these bridges 178 million times every single day. This matters because structurally deficient does not mean the bridge will collapse tomorrow, but it means the bridge has deteriorated to the point where load-carrying capacity is reduced, maintenance costs are escalating, and the risk of sudden failure is materially higher than for bridges in fair or good condition. When a structurally deficient bridge does fail, the consequences are catastrophic: the 2007 I-35W bridge collapse in Minneapolis killed 13 people and injured 145, and the economic disruption from the closed crossing lasted years. The deeper pain is that there is no credible timeline to fix these bridges. At the current pace of repair and replacement, ASCE estimates it would take over 40 years to clear the backlog. Meanwhile, bridges continue to deteriorate faster than they are being repaired, so the backlog is effectively growing. State DOTs know which bridges are worst, but they lack the funding and workforce to act. This problem persists because bridge funding in the US is fragmented across federal, state, and local governments, with no single entity accountable for ensuring every bridge meets minimum standards. The federal Highway Bridge Program provides formula funding, but states have wide discretion to spend it on other transportation priorities. Local governments own 56% of all bridges but receive a disproportionately small share of federal transportation dollars. In the first place, the structural root cause is that bridges are invisible infrastructure. Unlike potholes or congested highways, a deteriorating bridge looks fine until it doesn't. Voters and politicians do not rally around bridge maintenance because the failure mode is rare but catastrophic rather than frequent and visible, creating a classic underinvestment in low-probability, high-consequence risk.