Johnson County, IA

Johnson County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Johnson County, Iowa contains 317 public highway bridges. Roughly 33.4% are rated “Good,” 45.1% “Fair,” and 8.2% “Poor.” Poor means the lowest applicable deck, superstructure, substructure, or culvert rating is 4 or below on the 0–9 NBI scale. It is a condition category, not a live safety or closure decision.

Responsible agencies inspect covered bridges on risk-based intervals under current NBIS rules and submit inventory data to FHWA annually. The list below shows every NBI-tracked bridge in the county. Use the “Sort by” controls to change the ordering, and click any row for its reported inspection date, traffic count, and condition fields.

Source: FHWA National Bridge Inventory. See methodology for full definitions.