US Bridges

Forest Road over South Fork Canyon Creek

Good

Flathead County, Montana · Trumbull Creek Area · Structure no. 011007000010918

Built
2005
20 years old
Condition
Good
inspected July 2021
Type
Tee Beam
Prestressed Concrete
Length
42 ft
1 main span
Daily traffic
40
Owner
Federal
U.S. Forest Service

About this bridge

Forest Road over South Fork Canyon Creek is a prestressed concrete tee beam carrying Forest Road over South Fork Canyon Creek in Flathead County, Montana. It was built in 2005, so it is 20 years old, younger than the Montana average of 47 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 40 vehicles a day, projected to reach 60 by 2045. The structure is 42 ft (12.8 m) long and 17 ft wide. If it were closed, the detour would be 620.7 mi (999 km).

CarriesForest Road
CrossesSouth Fork Canyon Creek
LocationTrumbull Creek Area
RouteFederal Lands Road 9848
StateMontana
Coordinates48.48593, -114.22984
Functional classRural Local

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck8 Very GoodNo problems noted.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionJuly 2021
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation8: Equal to present desirable criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating50.7 US tons
Inventory rating38.9 US tons

Structure

Structure typeTee Beam
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans1
Design loadH 20
Structure length42 ft (12.8 m)
Longest span40 ft (12.2 m)
Deck width17 ft (5.3 m)
Roadway width15 ft (4.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic40 (—)
Projected traffic60 by 2045
Trucks—
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed620.7 mi (999 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerU.S. Forest Service
Maintained byU.S. Forest Service
Historic statusHistorical significance not determinable at this time
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Forest Road over South Fork Canyon Creek built?

It was built in 2005, making it 20 years old in 2025.

What condition is Forest Road over South Fork Canyon Creek in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in July 2021.

How much traffic does Forest Road over South Fork Canyon Creek carry?

About 40 vehicles per day (latest count).

How long is Forest Road over South Fork Canyon Creek?

The structure is 42 ft (12.8 m) long with a longest span of 40 ft (12.2 m) and a deck 17 ft wide.

Who owns Forest Road over South Fork Canyon Creek?

It is owned by the U.S. Forest Service.