I 15B ;us 91 over Blackfoot River
PoorBingham County, Idaho · In Blackfoot · Structure no. 000000000012090
- Built
- 1936
- 89 years old, rebuilt 1960
- Condition
- Poor
- inspected October 2024
- Type
- Tee Beam
- Concrete Continuous
- Length
- 106 ft
- 2 main spans
- Daily traffic
- 7,000
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
I 15B ;us 91 over Blackfoot River is a concrete continuous tee beam carrying I 15B ;us 91 over Blackfoot River in Bingham County, Idaho. It was built in 1936 and reconstructed in 1960, so it is 89 years old, older than the Idaho average of 45.3 years.
The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.
It carries about 7,000 vehicles a day, roughly 6% of them trucks, projected to reach 10,500 by 2042. The structure is 106 ft (32.3 m) long and 49 ft wide. If it were closed, the detour would be 0.6 mi (1 km).
Location
Open in Google MapsCondition and inspection
The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.
| Component | Rating | Meaning |
|---|---|---|
| Deck | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
| Superstructure | 4 Poor | Advanced section loss, deterioration, spalling or scour. |
| Substructure | 6 Satisfactory | Structural elements show some minor deterioration. |
| Channel and channel protection | 7 Good | Some minor problems. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was I 15B ;us 91 over Blackfoot River built?
It was built in 1936, making it 89 years old in 2025. It was reconstructed in 1960.
What condition is I 15B ;us 91 over Blackfoot River in?
The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in October 2024.
How much traffic does I 15B ;us 91 over Blackfoot River carry?
About 7,000 vehicles per day (2023 count), of which roughly 6% are trucks.
How long is I 15B ;us 91 over Blackfoot River?
The structure is 106 ft (32.3 m) long with a longest span of 37 ft (11.3 m) and a deck 49 ft wide.
Who owns I 15B ;us 91 over Blackfoot River?
It is owned by the State Highway Agency.