Structure 8072 · Oakland County, MI

Wattles RD over I-75

Carries Wattles RD over I-75, In Troy.

Overall conditionGood

Set by its lowest-rated component: Deck and Superstructure and Substructure at 8 of 9.

How ratings work
Decksets the rating8/9 · Very Good
Superstructuresets the rating8/9 · Very Good
Substructuresets the rating8/9 · Very Good
0 failed4 poor6 fair9 excellent

Elevation

Side view, colored by inspection rating
SEMI-TRUCK · 72 FT182 FT OVERALL25 FT0ELEVATION · LENGTHS TO SCALE
Deck 8/9Superstructure 8/9Substructure 8/9

182 ft end to end, longest span 99 ft: about 3 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.

Built20197 years old
Length182.4 ft55.6 m
Daily traffic—reported figure implausible
Last inspectedSeptember 2023every 24 months

Location

StateMichigan
CountyOakland
LocationIn Troy
CarriesWattles RD
CrossesI-75
Coordinates42.57698, -83.15896

Physical Characteristics

MaterialPrestressed Concrete
DesignStringer/Multi-beam
Total Length182.4 ft (55.6 m)
Max Span99.4 ft (30.3 m)
Deck Width68.9 ft (21 m)
Deck Area1167.6 sq m
Main Spans2
Year Built2019

Traffic

Avg Daily Traffic123,600 (2008)
That is about 61,800 vehicles per lane per day — beyond what any U.S. road carries (the busiest freeways run about 25,000–30,000). It is almost certainly a data-entry error in the National Bridge Inventory, so we leave this bridge out of traffic rankings.
Truck Traffic3%
Lanes On Bridge2
Lanes Under Bridge8

Inspection & Ownership

Last InspectionSeptember 2023
Inspection FrequencyEvery 24 months
OwnerState Highway Agency
Historical SignificanceBridge is not eligible for the National Register
Scour CriticalNot applicable
Structure Number000000000008072

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.

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