Structure I00090104+07801 · Missoula County, MT

I 90 over Int Orange Street

Carries I 90 over Int Orange Street, Missoula.

Overall conditionGood

Set by its lowest-rated component: Deck and Superstructure and Substructure at 7 of 9.

How ratings work
Decksets the rating7/9 · Good
Superstructuresets the rating7/9 · Good
Substructuresets the rating7/9 · Good
0 failed4 poor6 fair9 excellent

Elevation

Side view, colored by inspection rating
SEMI-TRUCK · 72 FT179 FT OVERALL25 FT0ELEVATION · LENGTHS TO SCALE
Deck 7/9Superstructure 7/9Substructure 7/9

179 ft end to end, longest span 72 ft: about 2 semi-trucks nose to tail. Lengths and the semi-truck on the deck are drawn to the same scale. Each part is colored by its latest inspection rating. The inventory records lengths but not heights or the layout of the shorter spans, so those are drawn as typical for a multi-beam bridge.

Built196660 years old
Length179.1 ft54.6 m
Daily traffic12,078counted 2023
Last inspectedJanuary 2025every 24 months

Location

StateMontana
CountyMissoula
LocationMissoula
CarriesI 90
CrossesInt Orange Street
Coordinates46.88025, -113.99269

Physical Characteristics

MaterialPrestressed Concrete
DesignStringer/Multi-beam
Total Length179.1 ft (54.6 m)
Max Span71.9 ft (21.9 m)
Deck Width38.4 ft (11.7 m)
Deck Area638.8 sq m
Main Spans3
Year Built1966

Traffic

Avg Daily Traffic12,078 (2023)
Truck Traffic10%
Lanes On Bridge2
Lanes Under Bridge2

Inspection & Ownership

Last InspectionJanuary 2025
Inspection FrequencyEvery 24 months
OwnerState Highway Agency
Historical SignificanceBridge is not eligible for the National Register
Scour CriticalNot applicable
Structure NumberI00090104+07801

How Bridge Ratings Work

Inspectors rate each major part of a bridge (the deck you drive on, the superstructure of beams that holds it up, and the substructure of piers and abutments beneath) on a 0–9 scale. A bridge's overall condition is its lowest of those ratings, so one deteriorated component makes the whole bridge "poor."

0Failed
1Imminent failure
2Critical
3Serious
4Poor
5Fair
6Satisfactory
7Good
8Very good
9Excellent
Good · lowest component 7–9
Fair · lowest component 5–6
Poor · lowest component 0–4

A poor rating is not a closure. It means the bridge is flagged for priority repair or replacement; bridges judged unsafe are closed or posted with weight limits. The waterway (channel) rating is reported, but it does not count toward the overall classification.

Nearby Bridges