Structure 7173 · Monroe County, MI

I-75 over Conrail Raisin R Front

Carries I-75 over Conrail Raisin R Front, In Monroe Over Front ST.

Overall conditionPoor

Set by its lowest-rated component: Superstructure at 4 of 9.

How ratings work
Deck6/9 · Satisfactory
Superstructuresets the rating4/9 · Poor
Substructure5/9 · Fair
Channelnot part of overall6/9 · Satisfactory
0 failed4 poor6 fair9 excellent

Elevation

Side view, colored by inspection rating
SEMI-TRUCK · 72 FT930 FT OVERALL200 FT0ELEVATION · LENGTHS TO SCALE
Deck 6/9Superstructure 4/9 · sets the ratingSubstructure 5/9

930 ft end to end, longest span 158 ft: about 2.6 football fields. 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 girder bridge.

Built1955rebuilt 2005
Length930.4 ft283.6 m
Daily traffic67,800counted 2019
Last inspectedJune 2024every 24 months

Location

StateMichigan
CountyMonroe
LocationIn Monroe Over Front ST
CarriesI-75
CrossesConrail Raisin R Front
Coordinates41.90433, -83.36997

Physical Characteristics

MaterialSteel
DesignGirder and Floorbeam
Total Length930.4 ft (283.6 m)
Max Span157.8 ft (48.1 m)
Deck Width113.5 ft (34.6 m)
Deck Area9812.6 sq m
Main Spans3
Year Built1955 (reconstructed 2005)

Traffic

Avg Daily Traffic67,800 (2019)
Truck Traffic25%
Lanes On Bridge6
Lanes Under Bridge2

Inspection & Ownership

Last InspectionJune 2024
Inspection FrequencyEvery 24 months
OwnerState Highway Agency
Historical SignificanceBridge is on the National Register of Historic Places
Scour Critical3 — Scour critical
Structure Number000000000007173

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