The United States has more than 620,000 bridges on public roads, from interstate highway spans to rural county crossings. Every bridge is inspected at least every two years under the Federal Highway Administration’s National Bridge Inspection Program, and each receives an overall condition rating — Good, Fair, or Poor — based on the structural state of its deck, superstructure, and substructure. Nationally, around 41,000 bridges — roughly 6.7% — are currently rated in poor condition.
The interactive US bridges map below plots all 620,000+ bridges from the FHWA National Bridge Inventory. Each bridge is color-coded: red for poor, amber for fair, and green for good. Click any cluster to zoom in, then click an individual bridge marker to see its route, the waterway or road it crosses, structural component ratings, year built, daily traffic count, and last inspection date. Use the condition checkboxes to filter by rating, or toggle to satellite view to see the bridge from above.
US Bridge Conditions: By the Numbers
- 620,000+ bridges on public roads across the 50 states and DC
- ~41,000 bridges (6.7%) rated in poor condition nationally
- ~308,000 bridges (49.6%) rated in fair condition
- ~272,000 bridges (43.8%) rated in good condition
- Bridges are inspected at least every 24 months under FHWA standards
- A bridge is rated poor when any of its three components — deck, superstructure, or substructure — scores 4 or below on the 0-9 NBI scale
Which States Have the Most Bridges in Poor Condition?
Bridge condition varies dramatically by state, reflecting differences in climate, bridge age, traffic loads, and investment in maintenance. States in the Midwest and Northeast tend to face the harshest conditions, with freeze-thaw cycles accelerating deck deterioration. The table below ranks all 51 states and DC by the share of bridges rated in poor condition.
| State | Total Bridges | Poor | Poor % | vs National Avg |
|---|---|---|---|---|
| Iowa | 23,716 | 4,423 | 18.6% | +178% |
| West Virginia | 7,345 | 1,307 | 17.8% | +165% |
| South Dakota | 5,883 | 945 | 16.1% | +140% |
| Maine | 2,542 | 392 | 15.4% | +130% |
| Rhode Island | 787 | 110 | 14.0% | +109% |
| Pennsylvania | 23,314 | 2,813 | 12.1% | +81% |
| Louisiana | 12,684 | 1,423 | 11.2% | +67% |
| North Dakota | 4,250 | 470 | 11.1% | +66% |
| Illinois | 26,927 | 2,563 | 9.5% | +42% |
| Missouri | 24,647 | 2,163 | 8.8% | +31% |
States With the Fewest Poor-Condition Bridges
| State | Total Bridges | Poor | Poor % |
|---|---|---|---|
| Nevada | 2,123 | 22 | 1.0% |
| Arizona | 8,587 | 95 | 1.1% |
| Delaware | 874 | 10 | 1.1% |
| Texas | 56,951 | 680 | 1.2% |
| Georgia | 15,090 | 263 | 1.7% |
What Does Poor Condition Actually Mean?
A bridge rated in poor condition is not necessarily unsafe or closed. The NBI rating reflects the structural condition of the components, not an immediate safety determination. Under FHWA rules, if any of a bridge’s three components — deck (the road surface), superstructure (the beams and trusses), or substructure (the piers and abutments) — scores 4 or below on the 0-to-9 NBI scale, the entire bridge receives a poor condition rating.
Bridges in poor condition are subject to load restrictions and intensive monitoring, and many remain open with weight limits in place. However, the condition rating is an important signal: poor-condition bridges carry higher maintenance and repair costs, and the older the structure and the higher the daily traffic, the more urgent the need for action.
Frequently Asked Questions
How often are US bridges inspected?
Under the FHWA National Bridge Inspection Standards, most bridges must be inspected at least once every 24 months. Bridges in especially poor condition or with known structural concerns may be inspected more frequently — sometimes every 6 or 12 months. Underwater inspections of substructure elements in rivers and coastal waters follow a separate schedule.
What is the difference between a structurally deficient and a poor-condition bridge?
The term “structurally deficient” was the FHWA’s older classification and included both bridges in poor condition and bridges with low load ratings or inadequate deck geometry. The FHWA replaced this terminology in 2018 with the simpler Good / Fair / Poor classification based directly on NBI element condition scores. All references to bridge condition on this map use the current Good/Fair/Poor system.
Where does this bridge data come from?
All bridge data is sourced from the FHWA National Bridge Inventory, published by the US Bureau of Transportation Statistics as part of the National Transportation Atlas Database (NTAD). The inventory is updated annually and contains location, condition, traffic, and ownership data for every bridge on public roads in the United States meeting the NBI size threshold (span of 20 feet or more).
Is it safe to drive over a bridge rated in poor condition?
State and local transportation departments are responsible for ensuring that bridges are safe or appropriately restricted. A poor condition rating triggers enhanced monitoring and may result in posted weight limits or lane restrictions, but it does not mean the bridge will collapse. If a bridge is found to be unsafe for any traffic, it is closed. That said, the accumulation of deferred maintenance across hundreds of thousands of bridges represents a significant long-term risk to both transportation reliability and public safety.
Explore Bridges by State
Each state page includes a state-filtered interactive map, condition breakdowns, the oldest bridges in the inventory, the most concerning bridges by traffic and rating, and a governance section explaining who is responsible for bridge maintenance in that state.
Alabama | Alaska | Arizona | Arkansas | California | Colorado | Connecticut | Delaware | District of Columbia | Florida | Georgia | Hawaii | Idaho | Illinois | Indiana | Iowa | Kansas | Kentucky | Louisiana | Maine | Maryland | Massachusetts | Michigan | Minnesota | Mississippi | Missouri | Montana | Nebraska | Nevada | New Hampshire | New Jersey | New Mexico | New York | North Carolina | North Dakota | Ohio | Oklahoma | Oregon | Pennsylvania | Rhode Island | South Carolina | South Dakota | Tennessee | Texas | Utah | Vermont | Virginia | Washington | West Virginia | Wisconsin | Wyoming
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