Structure I00090182+09191 · Powell County, MT

I 90 over Jr Grade Sep

Carries I 90 over Jr Grade Sep, 6.2m N Deer Lodge.

Overall conditionFair

Set by its lowest-rated component: Deck and Superstructure and Substructure at 6 of 9.

How ratings work
Decksets the rating6/9 · Satisfactory
Superstructuresets the rating6/9 · Satisfactory
Substructuresets the rating6/9 · Satisfactory
0 failed4 poor6 fair9 excellent

Elevation

Side view, colored by inspection rating
23 FT OVERALL25 FT0ELEVATION · LENGTHS TO SCALE
Deck 6/9Superstructure 6/9Substructure 6/9

23 ft end to end. Lengths are drawn to scale; at this length a semi-truck would be a speck. 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 slab bridge.

Built1961rebuilt 1974
Length22.6 ft6.9 m
Daily traffic10,463counted 2023
Last inspectedJune 2024every 24 months

Location

StateMontana
CountyPowell
Location6.2m N Deer Lodge
CarriesI 90
CrossesJr Grade Sep
Coordinates46.44039, -112.72350

Physical Characteristics

MaterialConcrete
DesignSlab
Total Length22.6 ft (6.9 m)
Max Span20.0 ft (6.1 m)
Deck Width133.9 ft (40.8 m)
Deck Area281.5 sq m
Main Spans1
Year Built1961 (reconstructed 1974)

Traffic

Avg Daily Traffic10,463 (2023)
Truck Traffic20%
Lanes On Bridge4
Lanes Under Bridge2

Inspection & Ownership

Last InspectionJune 2024
Inspection FrequencyEvery 24 months
OwnerState Highway Agency
Historical SignificanceBridge is not eligible for the National Register
Scour CriticalNot applicable
Structure NumberI00090182+09191

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