IRR - US 89 over Blacktail Creek
PoorPondera County, Montana · 16M NW Valier · Structure no. P00003087+03951
- Built
- 1965
- 60 years old
- Condition
- Poor
- inspected September 2023
- Type
- Stringer/Multi-beam or Girder
- Prestressed Concrete
- Length
- 145 ft
- 2 main spans
- Daily traffic
- 1,012
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
IRR - US 89 over Blacktail Creek is a prestressed concrete stringer/multi-beam or girder carrying IRR - US 89 over Blacktail Creek in Pondera County, Montana. It was built in 1965, so it is 60 years old, older than the Montana average of 47 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 1,012 vehicles a day, roughly 5% of them trucks, projected to reach 1,063 by 2043. The structure is 145 ft (44.2 m) long and 37 ft wide. If it were closed, the detour would be 72.7 mi (117 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 | 4 Poor | Advanced section loss, deterioration, spalling or scour. |
| Superstructure | 8 Very Good | No problems noted. |
| Substructure | 7 Good | Some minor problems. |
| Channel and channel protection | 7 Good | Some minor problems. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was IRR - US 89 over Blacktail Creek built?
It was built in 1965, making it 60 years old in 2025.
What condition is IRR - US 89 over Blacktail Creek 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 September 2023.
How much traffic does IRR - US 89 over Blacktail Creek carry?
About 1,012 vehicles per day (2023 count), of which roughly 5% are trucks.
How long is IRR - US 89 over Blacktail Creek?
The structure is 145 ft (44.2 m) long with a longest span of 71 ft (21.6 m) and a deck 37 ft wide.
Who owns IRR - US 89 over Blacktail Creek?
It is owned by the State Highway Agency.