US Bridges

Forest Road over Graves Creek

Poor

Flathead County, Montana · Graves Creek Area · Structure no. 011006000000107

Built
1970
55 years old
Condition
Poor
inspected September 2023
Type
Stringer/Multi-beam or Girder
Wood or Timber
Length
40 ft
1 main span
Daily traffic
10
1992 count
Owner
Federal
U.S. Forest Service

About this bridge

Forest Road over Graves Creek is a wood or timber stringer/multi-beam or girder carrying Forest Road over Graves Creek in Flathead County, Montana. It was built in 1970, so it is 55 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 10 vehicles a day, projected to reach 15 by 2045. The structure is 40 ft (12.2 m) long and 15 ft wide. If it were closed, the detour would be 98.2 mi (158 km).

Location

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CarriesForest Road
CrossesGraves Creek
LocationGraves Creek Area
RouteFederal Lands Road 9797
CountyFlathead County
StateMontana
Coordinates48.13115, -113.82275
Functional classRural Local

Condition and inspection

Poor

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.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Channel and channel protection9 ExcellentNo problems noted.
Last inspectionSeptember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; action required to protect exposed foundations
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating32.5 US tons
Inventory rating25 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialWood or Timber
DeckWood or timber
Main spans1
Design loadH 20
Structure length40 ft (12.2 m)
Longest span39 ft (11.9 m)
Deck width15 ft (4.7 m)
Roadway width14 ft (4.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic10 (1992)
Projected traffic15 by 2045
Trucks—
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed98.2 mi (158 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 Graves Creek built?

It was built in 1970, making it 55 years old in 2025.

What condition is Forest Road over Graves Creek 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 2023.

How much traffic does Forest Road over Graves Creek carry?

About 10 vehicles per day (1992 count).

How long is Forest Road over Graves Creek?

The structure is 40 ft (12.2 m) long with a longest span of 39 ft (11.9 m) and a deck 15 ft wide.

Who owns Forest Road over Graves Creek?

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