US Bridges

Ruby Road over Middle Fk Ruby Rive

Fair

Madison County, Montana · M Fk Ruby River · Structure no. 010206000000025

Built
1947
78 years old
Condition
Fair
inspected August 2024
Type
Stringer/Multi-beam or Girder
Wood or Timber
Length
36 ft
1 main span
Daily traffic
50
1993 count
Owner
Federal
U.S. Forest Service

About this bridge

Ruby Road over Middle Fk Ruby Rive is a wood or timber stringer/multi-beam or girder carrying Ruby Road over Middle Fk Ruby Rive in Madison County, Montana. It was built in 1947, so it is 78 years old, older than the Montana average of 47 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 50 vehicles a day, projected to reach 75 by 2045. The structure is 36 ft (11.1 m) long and 13 ft wide. If it were closed, the detour would be 98.2 mi (158 km).

Location

Open in Google Maps
CarriesRuby Road
CrossesMiddle Fk Ruby Rive
LocationM Fk Ruby River
RouteFederal Lands Road 100
CountyMadison County
StateMontana
Coordinates44.90689, -111.99989
Functional classRural Local

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionAugust 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating23.6 US tons
Inventory rating18.2 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialWood or Timber
DeckWood or timber
Main spans1
Design loadH 20
Structure length36 ft (11.1 m)
Longest span35 ft (10.7 m)
Deck width13 ft (4.1 m)
Roadway width12 ft (3.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic50 (1993)
Projected traffic75 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 Ruby Road over Middle Fk Ruby Rive built?

It was built in 1947, making it 78 years old in 2025.

What condition is Ruby Road over Middle Fk Ruby Rive 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 August 2024.

How much traffic does Ruby Road over Middle Fk Ruby Rive carry?

About 50 vehicles per day (1993 count).

How long is Ruby Road over Middle Fk Ruby Rive?

The structure is 36 ft (11.1 m) long with a longest span of 35 ft (10.7 m) and a deck 13 ft wide.

Who owns Ruby Road over Middle Fk Ruby Rive?

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