NF-6639 RD over Boulder River 041
PoorPark County, Montana · 35M S Springdale · Structure no. L34210004+06001
- Built
- 1933
- 92 years old
- Condition
- Poor
- inspected September 2024
- Type
- Truss - Thru
- Steel
- Length
- 99 ft
- 1 main span
- Daily traffic
- 157
- 2023 count
- Owner
- County
- County Highway Agency
About this bridge
NF-6639 RD over Boulder River 041 is a steel truss - thru carrying NF-6639 RD over Boulder River 041 in Park County, Montana. It was built in 1933, so it is 92 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 157 vehicles a day, roughly 17% of them trucks, projected to reach 165 by 2043. The structure is 99 ft (30.2 m) long and 13 ft wide. If it were closed, the detour would be 123.7 mi (199 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 | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
| Superstructure | 6 Satisfactory | Structural elements show some minor deterioration. |
| Substructure | 4 Poor | Advanced section loss, deterioration, spalling or scour. |
| Channel and channel protection | 4 Poor | Advanced section loss, deterioration, spalling or scour. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was NF-6639 RD over Boulder River 041 built?
It was built in 1933, making it 92 years old in 2025.
What condition is NF-6639 RD over Boulder River 041 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 2024.
How much traffic does NF-6639 RD over Boulder River 041 carry?
About 157 vehicles per day (2023 count), of which roughly 17% are trucks.
How long is NF-6639 RD over Boulder River 041?
The structure is 99 ft (30.2 m) long with a longest span of 80 ft (24.4 m) and a deck 13 ft wide.
Who owns NF-6639 RD over Boulder River 041?
It is owned by the County Highway Agency.