Disclaimer & Responsible Use

PlainBridge is a free informational resource that makes the public Federal Highway Administration National Bridge Inventory easier to read. It is not an engineering assessment, not a safety certification, and not professional advice. Nothing here tells you whether a specific bridge is safe to drive across. Use it as a starting point for understanding public inspection data, not as the final word on a structure's condition.

"Structurally deficient" does not mean "unsafe"

This is the single most important thing to understand about NBI data. A bridge classified as structurally deficient is one whose deck, superstructure, substructure, or culvert is rated in poor condition (4 or below on the 0–9 NBI scale) and that therefore needs repair, rehabilitation, or closer monitoring. It does not mean the bridge is dangerous or about to fail. Structurally deficient bridges remain open to traffic, are inspected more frequently, and may carry posted weight limits. Engineers, not a condition code, decide whether a bridge stays open. If a structure were judged unsafe, the responsible agency would post, restrict, or close it.

Informational only, not engineering advice

Nothing on PlainBridge constitutes engineering, structural, legal, or safety advice, and using the site does not create any professional relationship. Bridge safety is determined by licensed inspectors and engineers working for the agency that owns the structure. For an authoritative judgment about a specific bridge, contact the relevant state Department of Transportation or local public-works agency. For the official record, consult the FHWA National Bridge Inventory directly.

What these figures are, and are not

The condition ratings on PlainBridge are a snapshot from the most recent inspection a state submitted, not a real-time measurement. Inspections can be up to 24 months old, and condition ratings involve professional judgment that varies between inspectors — a bridge rated 5 by one inspector might be rated 4 or 6 by another. The inventory load rating is an engineering reference value, not a guarantee of capacity for any particular vehicle. A bridge's true condition can change between inspection cycles because of weather, traffic loads, or maintenance work.

Data freshness and accuracy

The figures here reflect the most recent annual NBI release available to us, named and dated through our methodology and on the pages themselves. We work to keep the data accurate and to fix errors at the source, but we cannot guarantee it is complete, current, or free of upstream limitations such as missing fields or a lagging inspection cycle. If you spot a figure that looks wrong, please report it through our corrections process.

Reporting an actual bridge problem

PlainBridge cannot dispatch inspectors or repairs and is not a reporting channel for hazards. If you see a visible problem with a bridge — debris, damage, a structural concern, or an immediate danger — contact your state Department of Transportation, call the non-emergency line for local authorities, or dial 911 in an emergency. Our guide to reporting an unsafe bridge explains the right channels.

No affiliation

PlainBridge is an independent publisher. It is not affiliated with, endorsed by, or operated by the Federal Highway Administration, the U.S. Department of Transportation, or any state agency. Outbound links to official sources are provided for verification and do not imply any partnership.

Questions

Questions about how to use this data, or about a specific figure, are welcome at hello@plainbridges.com. See also our editorial & corrections policy and methodology.