IRR BIA RTE 18 over Blackduck River
FairBeltrami County, Minnesota · 12 KM NE of Redby · Structure no. 00000000000F124
- Built
- 1976
- 49 years old
- Condition
- Fair
- inspected September 2023
- Type
- Stringer/Multi-beam or Girder
- Prestressed Concrete
- Length
- 337 ft
- 5 main spans
- Daily traffic
- 400
- 2023 count
- Owner
- Federal
- Bureau of Indian Affairs
About this bridge
IRR BIA RTE 18 over Blackduck River is a prestressed concrete stringer/multi-beam or girder carrying IRR BIA RTE 18 over Blackduck River in Beltrami County, Minnesota. It was built in 1976, so it is 49 years old, older than the Minnesota average of 38.5 years.
The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 6 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.
It carries about 400 vehicles a day, roughly 20% of them trucks, projected to reach 600 by 2043. The structure is 337 ft (102.7 m) long and 35 ft wide. If it were closed, the detour would be 19.9 mi (32 km).
Location
Open in Google MapsCondition and inspection
The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.
| Component | Rating | Meaning |
|---|---|---|
| Deck | 6 Satisfactory | Structural elements show some minor deterioration. |
| Superstructure | 7 Good | Some minor problems. |
| Substructure | 7 Good | Some minor problems. |
| Channel and channel protection | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was IRR BIA RTE 18 over Blackduck River built?
It was built in 1976, making it 49 years old in 2025.
What condition is IRR BIA RTE 18 over Blackduck River in?
The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in September 2023.
How much traffic does IRR BIA RTE 18 over Blackduck River carry?
About 400 vehicles per day (2023 count), of which roughly 20% are trucks.
How long is IRR BIA RTE 18 over Blackduck River?
The structure is 337 ft (102.7 m) long with a longest span of 75 ft (22.9 m) and a deck 35 ft wide.
Who owns IRR BIA RTE 18 over Blackduck River?
It is owned by the Bureau of Indian Affairs.