IRR BIA RTE 18 over Colorado River
FairLa Paz County, Arizona · 2.6 MI W of BIA RTE 1 · Structure no. 00000000000H042
- Built
- 1981
- 44 years old
- Condition
- Fair
- inspected February 2024
- Type
- Stringer/Multi-beam or Girder
- Prestressed Concrete Continuous
- Length
- 560 ft
- 6 main spans
- Daily traffic
- 274
- 2024 count
- Owner
- Federal
- Bureau of Indian Affairs
About this bridge
IRR BIA RTE 18 over Colorado River is a prestressed concrete continuous stringer/multi-beam or girder carrying IRR BIA RTE 18 over Colorado River in La Paz County, Arizona. It was built in 1981, so it is 44 years old, younger than the Arizona average of 47.8 years.
The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 5 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 274 vehicles a day, roughly 22% of them trucks, projected to reach 410 by 2044. The structure is 560 ft (170.7 m) long and 34 ft wide. If it were closed, the detour would be 42.9 mi (69 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 | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
| Superstructure | 7 Good | Some minor problems. |
| 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 IRR BIA RTE 18 over Colorado River built?
It was built in 1981, making it 44 years old in 2025.
What condition is IRR BIA RTE 18 over Colorado 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 February 2024.
How much traffic does IRR BIA RTE 18 over Colorado River carry?
About 274 vehicles per day (2024 count), of which roughly 22% are trucks.
How long is IRR BIA RTE 18 over Colorado River?
The structure is 560 ft (170.7 m) long with a longest span of 93 ft (28.4 m) and a deck 34 ft wide.
Who owns IRR BIA RTE 18 over Colorado River?
It is owned by the Bureau of Indian Affairs.