IRR - SR 480 over Missouri River

Fair Condition58 years old80 vehicles/day

Location

StateMontana
CountyRichland
Location9m SW Brockton
CarriesIRR - SR 480
CrossesMissouri River
Coordinates48.06400, -105.03140

Condition Ratings

Overall ConditionFair
Deck6 (Satisfactory)
Superstructure5 (Fair)
Substructure6 (Satisfactory)
Channel/Waterway6 (Satisfactory)
Scour Critical5 — Stable for scour

Physical Characteristics

MaterialSteel Continuous
DesignGirder and Floorbeam
Total Length1056.8 ft (322.1 m)
Max Span265.7 ft (81 m)
Deck Width33.1 ft (10.1 m)
Deck Area3253.2 sq m
Main Spans4
Year Built1968

Traffic

Avg Daily Traffic80 (2023)
Truck Traffic4%
Lanes On Bridge2

Inspection & Ownership

Last Inspection523
Inspection FrequencyEvery 24 months
OwnerState Highway Agency
Historical SignificanceBridge is not eligible for the National Register
Structure NumberS00480003+00001