I 15 over Boulder River

Fair Condition41 years old3,182 vehicles/day

Location

StateMontana
CountyJefferson
Location1.9m S Basin
CarriesI 15
CrossesBoulder River
Coordinates46.26353, -112.28476

Condition Ratings

Overall ConditionFair
Deck7 (Good)
Superstructure7 (Good)
Substructure6 (Satisfactory)
Channel/Waterway8 (Very Good)
Scour Critical8 — Stable, low risk

Physical Characteristics

MaterialPrestressed Concrete
DesignStringer/Multi-beam
Total Length125.0 ft (38.1 m)
Max Span49.9 ft (15.2 m)
Deck Width84.3 ft (25.7 m)
Deck Area979.2 sq m
Main Spans3
Year Built1985

Traffic

Avg Daily Traffic3,182 (2023)
Truck Traffic16%
Lanes On Bridge4

Inspection & Ownership

Last Inspection225
Inspection FrequencyEvery 24 months
OwnerState Highway Agency
Historical SignificanceBridge is not eligible for the National Register
Structure NumberI00015154+08131

Nearby Bridges