US Bridges

Timberline RD over Big Spring Creek 134

Good

Fergus County, Montana · 4M SE Lewistown · Structure no. L14371000+01001

Built
2012
13 years old
Condition
Good
inspected August 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
57 ft
1 main span
Daily traffic
100
2025 count
Owner
County
County Highway Agency

About this bridge

Timberline RD over Big Spring Creek 134 is a steel stringer/multi-beam or girder carrying Timberline RD over Big Spring Creek 134 in Fergus County, Montana. It was built in 2012, so it is 13 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 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 100 vehicles a day, roughly 3% of them trucks, projected to reach 100 by 2040. The structure is 57 ft (17.4 m) long and 26 ft wide. If it were closed, the detour would be 123.7 mi (199 km).

Location

Open in Google Maps
CarriesTimberline RD
CrossesBig Spring Creek 134
Location4M SE Lewistown
RouteCounty Highway 14371
CountyFergus County
StateMontana
Coordinates47.03811, -109.40195
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
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionAugust 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation7: Better than present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating45 US tons
Inventory rating34.6 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, precast panels
Main spans1
Design loadHL 93
Structure length57 ft (17.4 m)
Longest span54 ft (16.4 m)
Deck width26 ft (8 m)
Roadway width23 ft (6.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic100 (2025)
Projected traffic100 by 2040
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed123.7 mi (199 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$140,000
NavigationNo navigation control on waterway

Frequently asked questions

When was Timberline RD over Big Spring Creek 134 built?

It was built in 2012, making it 13 years old in 2025.

What condition is Timberline RD over Big Spring Creek 134 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 August 2024.

How much traffic does Timberline RD over Big Spring Creek 134 carry?

About 100 vehicles per day (2025 count), of which roughly 3% are trucks.

How long is Timberline RD over Big Spring Creek 134?

The structure is 57 ft (17.4 m) long with a longest span of 54 ft (16.4 m) and a deck 26 ft wide.

Who owns Timberline RD over Big Spring Creek 134?

It is owned by the County Highway Agency.