Structure 8021 · Oakland County, MI

I-75 NB over Clarkston RD

Carries I-75 NB over Clarkston RD, 1.1 Mi SE Of M-15.

Overall conditionPoor

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

How ratings work
Decksets the rating4/9 · Poor
Superstructure6/9 · Satisfactory
Substructure5/9 · Fair
0 failed4 poor6 fair9 excellent

Elevation

Side view, colored by inspection rating
CAR · 15 FT109 FT OVERALL25 FT0ELEVATION · LENGTHS TO SCALE
Deck 4/9 · sets the ratingSuperstructure 6/9Substructure 5/9

109 ft end to end, longest span 40 ft. Lengths and the car 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.

Built1962rebuilt 1988
Length108.6 ft33.1 m
Daily traffic35,763counted 2007
Last inspectedMarch 2023every 24 months

Location

StateMichigan
CountyOakland
Location1.1 Mi SE Of M-15
CarriesI-75 NB
CrossesClarkston RD
Coordinates42.74568, -83.39980

Physical Characteristics

MaterialSteel
DesignStringer/Multi-beam
Total Length108.6 ft (33.1 m)
Max Span40.4 ft (12.3 m)
Deck Width62.0 ft (18.9 m)
Deck Area625.6 sq m
Main Spans3
Year Built1962 (reconstructed 1988)

Traffic

Avg Daily Traffic35,763 (2007)
Truck Traffic5%
Lanes On Bridge3
Lanes Under Bridge2

Inspection & Ownership

Last InspectionMarch 2023
Inspection FrequencyEvery 24 months
OwnerState Highway Agency
Historical SignificanceBridge is not eligible for the National Register
Scour CriticalNot applicable
Structure Number000000000008021

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