North 55th Street over Boulder Creek
FairBoulder County, Colorado · 0.1 MI N of Flatiron Pkwy · Structure no. BOLD-08-0.30-02
- Built
- 1985
- 40 years old
- Condition
- Fair
- inspected February 2025
- Type
- Stringer/Multi-beam or Girder
- Prestressed Concrete Continuous
- Length
- 200 ft
- 2 main spans
- Daily traffic
- 11,600
- 2023 count
- Owner
- City
- City or Municipal Highway Agency
About this bridge
North 55th Street over Boulder Creek is a prestressed concrete continuous stringer/multi-beam or girder carrying North 55th Street over Boulder Creek in Boulder County, Colorado. It was built in 1985, so it is 40 years old, younger 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 11,600 vehicles a day, roughly 10% of them trucks, projected to reach 13,920 by 2043. The structure is 200 ft (61.1 m) long and 72 ft wide. If it were closed, the detour would be 1.9 mi (3 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 | 8 Very Good | No problems noted. |
| Substructure | 7 Good | Some minor problems. |
| Channel and channel protection | 8 Very Good | No problems noted. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was North 55th Street over Boulder Creek built?
It was built in 1985, making it 40 years old in 2025.
What condition is North 55th Street over Boulder Creek 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 2025.
How much traffic does North 55th Street over Boulder Creek carry?
About 11,600 vehicles per day (2023 count), of which roughly 10% are trucks.
How long is North 55th Street over Boulder Creek?
The structure is 200 ft (61.1 m) long with a longest span of 94 ft (28.7 m) and a deck 72 ft wide.
Who owns North 55th Street over Boulder Creek?
It is owned by the City or Municipal Highway Agency.