US Bridges

IRR - S 24 over Drainage

Fair

Valley County, Montana · 15M S Opheim · Structure no. P00031034+09421

Built
1939
86 years old
Condition
Fair
inspected October 2024
Type
Stringer/Multi-beam or Girder
Wood or Timber
Length
58 ft
3 main spans
Daily traffic
292
2023 count
Owner
State
State Highway Agency

About this bridge

IRR - S 24 over Drainage is a wood or timber stringer/multi-beam or girder carrying IRR - S 24 over Drainage in Valley County, Montana. It was built in 1939, so it is 86 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.

It carries about 292 vehicles a day, roughly 23% of them trucks, projected to reach 307 by 2043. The structure is 58 ft (17.7 m) long and 26 ft wide. If it were closed, the detour would be 123.7 mi (199 km).

Location

Open in Google Maps
CarriesIRR - S 24
CrossesDrainage
Location15M S Opheim
RouteState Highway 24
CountyValley County
StateMontana
Coordinates48.65128, -106.47928
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.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection7 GoodSome minor problems.
Last inspectionOctober 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 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 rating37 US tons
Inventory rating26 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialWood or Timber
DeckWood or timber
Main spans3
Design loadH 15
Structure length58 ft (17.7 m)
Longest span19 ft (5.8 m)
Deck width26 ft (7.9 m)
Roadway width24 ft (7.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic292 (2023)
Projected traffic307 by 2043
Trucks23%
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 IRR - S 24 over Drainage built?

It was built in 1939, making it 86 years old in 2025.

What condition is IRR - S 24 over Drainage 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 October 2024.

How much traffic does IRR - S 24 over Drainage carry?

About 292 vehicles per day (2023 count), of which roughly 23% are trucks.

How long is IRR - S 24 over Drainage?

The structure is 58 ft (17.7 m) long with a longest span of 19 ft (5.8 m) and a deck 26 ft wide.

Who owns IRR - S 24 over Drainage?

It is owned by the State Highway Agency.