SH 257 Ml over Big Thompson River
FairWeld County, Colorado · 0.8 MI No of JCT SH 60 · Structure no. C-17-Z
- Built
- 1961
- 64 years old
- Condition
- Fair
- inspected September 2023
- Type
- Tee Beam
- Concrete
- Length
- 166 ft
- 3 main spans
- Daily traffic
- 8,500
- 2020 count
- Owner
- State
- State Highway Agency
About this bridge
SH 257 Ml over Big Thompson River is a concrete tee beam carrying SH 257 Ml over Big Thompson River in Weld County, Colorado. It was built in 1961, so it is 64 years old, older than the Colorado average of 42.2 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 8,500 vehicles a day, roughly 9% of them trucks, projected to reach 15,810 by 2040. The structure is 166 ft (50.6 m) long and 32 ft wide. If it were closed, the detour would be 3.7 mi (6 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 | 6 Satisfactory | Structural elements show some minor deterioration. |
| Substructure | 6 Satisfactory | Structural elements show some minor deterioration. |
| 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 SH 257 Ml over Big Thompson River built?
It was built in 1961, making it 64 years old in 2025.
What condition is SH 257 Ml over Big Thompson 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 SH 257 Ml over Big Thompson River carry?
About 8,500 vehicles per day (2020 count), of which roughly 9% are trucks.
How long is SH 257 Ml over Big Thompson River?
The structure is 166 ft (50.6 m) long with a longest span of 54 ft (16.5 m) and a deck 32 ft wide.
Who owns SH 257 Ml over Big Thompson River?
It is owned by the State Highway Agency.