Analyzing deck conditions, superstructure ratings, and bad puns...
Analyzing deck conditions, superstructure ratings, and bad puns...
Infrastructure Grade
Infrastructure Report Card
5.4% of bridges in poor condition
Total Bridges
4,646
Poor Condition
250(5.4%)
Avg Bridge Age
46 yrs
Trend
Stable
| Metric | Idaho | National Avg | Trend |
|---|---|---|---|
| % Poor Condition | 5.4% | 6.7% | Stable |
| vs. National Average | -1.3 pts | -- | -- |
| Average Bridge Age | 46 yrs | 48 yrs | -- |
| Good or Better | 2,474(53.3%) | -- | -- |
Grade Scale
Percentage of bridges in poor condition over time. The dashed line shows the national average for comparison.
Total Bridges
4,646
Poor Condition
250(5.4%)
Average Age
46 yrs
Daily Crossings
15.4M
Good or Better
2,474(53.3%)
These bridges have at least one major component rated "5" (Fair) — one step above the poor threshold. Sorted by daily traffic to highlight highest-impact structures at risk.
| Bridge | Location | Deck | Super | Sub | Daily Traffic |
|---|---|---|---|---|---|
| I 84 ;US 20-26 | Canyon County | 5 | 6 | 6 | 58,000 |
| SH 55;EAGLE ROAD | Ada County | 6 | 5 | 6 | 58,000 |
| US 20 | Bonneville County | 6 | 5 | 6 | 38,000 |
| US 20 | Ada County | 5 | 6 | 6 | 35,500 |
| US 95 | Kootenai County | 5 | 5 | 5 | 33,500 |
| STC8223;NORTHSIDE | Canyon County | 6 | 5 | 6 | 29,000 |
| US 20 EB-WB | Jefferson County | 7 | 5 | 6 | 28,500 |
| SMA 7406;PANCHERI | Bonneville County | 5 | 5 | 6 | 26,000 |
| SMA 7563;OVERLAND | Ada County | 5 | 5 | 7 | 26,000 |
| SMA9463;FIVE MILE | Ada County | 7 | 5 | 6 | 24,000 |
| STP8393;FRANKLIN B | Canyon County | 5 | 6 | 6 | 22,000 |
| US 12 | Nez Perce County | 6 | 5 | 6 | 21,000 |
| I 15B ;BROADWAY ST | Bonneville County | 6 | 5 | 6 | 20,500 |
| US 26 EBL & WBL | Bingham County | 6 | 6 | 5 | 18,000 |
| I 15B ;BROADWAY ST | Bonneville County | 6 | 6 | 5 | 18,000 |
The 10 bridges in poorest condition, ranked by lowest sufficiency rating.
over CDA RIVER;SPRINGSTON BR
over REYNOLDS CREEK
over BEAR RIVER;E.WESTON BR.
over S.FK.COEUR DALENE RIVER
over N.FK.EAST RIVER
over CO.RD.;STODDARD CREEK IC
over CLOVER CREEK
over THIRD FK.CHIEF EAGLE EYE
over M.F.CLWATER R.;E.KOOSKIA
over WEISER RIVER
States with similar infrastructure profiles, ranked by percentage of bridges in poor condition.
Grading: Grades are based on the percentage of bridges classified as "poor condition." A bridge is in poor condition when at least one major component (deck, superstructure, or substructure) is rated 4 or below on the NBI 0-9 scale.
Data Source: Federal Highway Administration (FHWA) National Bridge Inventory (NBI). Data is updated annually. BridgeStats is not affiliated with or endorsed by the FHWA.
Watchlist Criteria: Bridges with any component rated "5" (Fair) are one step from the poor threshold of 4 and are flagged for monitoring. These bridges are not yet in poor condition but may deteriorate without maintenance.