US Bridges

S 81 over Coffee Creek

FairPosted for load

Fergus County, Montana · Coffee Creek · Structure no. P00081006+00921

Built
1952
73 years old
Condition
Fair
inspected September 2024
Type
Stringer/Multi-beam or Girder
Wood or Timber
Length
38 ft
2 main spans
Daily traffic
347
2023 count
Owner
State
State Highway Agency

About this bridge

S 81 over Coffee Creek is a wood or timber stringer/multi-beam or girder carrying S 81 over Coffee Creek in Fergus County, Montana. It was built in 1952, so it is 73 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 5 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. Its operating status is: posted for load restriction.

It carries about 347 vehicles a day, roughly 9% of them trucks, projected to reach 364 by 2043. The structure is 38 ft (11.6 m) long and 26 ft wide. If it were closed, the detour would be 123.7 mi (199 km).

Location

Open in Google Maps
CarriesS 81
CrossesCoffee Creek
LocationCoffee Creek
RouteState Highway 81
CountyFergus County
StateMontana
Coordinates47.34622, -110.08048
Functional classRural Minor Arterial

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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusPosted for load 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 geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating33 US tons
Inventory rating21.1 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialWood or Timber
DeckWood or timber
Main spans2
Design loadH 15
Structure length38 ft (11.6 m)
Longest span19 ft (5.8 m)
Deck width26 ft (7.9 m)
Roadway width25 ft (7.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic347 (2023)
Projected traffic364 by 2043
Trucks9%
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

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was S 81 over Coffee Creek built?

It was built in 1952, making it 73 years old in 2025.

What condition is S 81 over Coffee Creek 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 September 2024.

How much traffic does S 81 over Coffee Creek carry?

About 347 vehicles per day (2023 count), of which roughly 9% are trucks.

How long is S 81 over Coffee Creek?

The structure is 38 ft (11.6 m) long with a longest span of 19 ft (5.8 m) and a deck 26 ft wide.

Who owns S 81 over Coffee Creek?

It is owned by the State Highway Agency.