Bridges
| Bridges in the National Bridge Inventory | 4,645 |
|---|---|
| Good condition | 1,644 (35.4%) |
| Fair condition | 2,753 (59.3%) |
| Poor condition | 248 (5.3%) |
| Total deck area | 19,943,466 sq ft |
| Deck area in poor condition | 650,973 sq ft (3.3%) |
Idaho ranks 28 of 51 (states plus DC) for the share of bridges in poor condition, where 1 is the highest share. Nationally, 6.6% of bridges are rated poor.
With a poor share close to the national rate, expect a steady mix of replacement, rehabilitation and preservation work. Fair-rated bridges (2,753 here) are the ones most likely to slip to poor without timely work, which is why many DOTs fund preservation and inspection contracts alongside replacements.
ASCE report card
The ASCE Idaho Section gave the state an overall grade of C in its 2025 report card. Read the full report.
| Category | Grade |
|---|---|
| Aviation | D+ |
| Bridges | C- |
| Dams | C |
| Drinking Water | C+ |
| Energy | C+ |
| Roads | C |
| Schools | D+ |
| Transit | C- |
| Wastewater | C+ |
Low-graded categories are where owners should expect agencies and utilities to push capital programs, and where grant applications tend to cluster.
More on Idaho for firm owners
- Idaho DOT prequalification and procurement
- Idaho PE licensure and PDH rules
- Idaho civil engineer salaries
- Accredited programs in Idaho
- Federal funding programs
Sources: Federal Highway Administration, National Bridge Inventory, 2026 Bridge Condition by Highway System (fhwa.dot.gov); ASCE Infrastructure Report Card state reports (infrastructurereportcard.org), produced by ASCE state sections in the year shown.
