US Bridges

I-275 NB over Tonquish CR

Good

Wayne County, Michigan · 3.5 MI SE of Plymouth · Structure no. 000000000011957

Built
1972
53 years old
Condition
Good
inspected October 2024
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
35 ft
1 main span
Daily traffic
63,759
2007 count
Owner
State
State Highway Agency

About this bridge

I-275 NB over Tonquish CR is a prestressed concrete stringer/multi-beam or girder carrying I-275 NB over Tonquish CR in Wayne County, Michigan. It was built in 1972, so it is 53 years old, older than the Michigan average of 48.3 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 63,759 vehicles a day, roughly 7% of them trucks, projected to reach 76,050 by 2042. The structure is 35 ft (10.7 m) long and 56 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesI-275 NB
CrossesTonquish CR
Location3.5 MI SE of Plymouth
RouteInterstate 275
Coordinates42.33497, -83.44311
Functional classUrban Principal Arterial - Interstate

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck8 Very GoodNo problems noted.
Superstructure8 Very GoodNo problems noted.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionOctober 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating83.6 US tons
Inventory rating50 US tons

Structure

MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20 + Mod
Structure length35 ft (10.7 m)
Longest span31 ft (9.6 m)
Deck width56 ft (17 m)
Roadway width52 ft (16 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic63,759 (2007)
Projected traffic76,050 by 2042
Trucks7%
Lanes on structure3
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was I-275 NB over Tonquish CR built?

It was built in 1972, making it 53 years old in 2025.

What condition is I-275 NB over Tonquish CR in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in October 2024.

How much traffic does I-275 NB over Tonquish CR carry?

About 63,759 vehicles per day (2007 count), of which roughly 7% are trucks.

How long is I-275 NB over Tonquish CR?

The structure is 35 ft (10.7 m) long with a longest span of 31 ft (9.6 m) and a deck 56 ft wide.

Who owns I-275 NB over Tonquish CR?

It is owned by the State Highway Agency.