US Bridges

Mill ST over I-75 NB

Fair

Otsego County, Michigan · NW Lts of Vanderbilt · Structure no. 000000000008683

Built
1962
63 years old
Condition
Fair
inspected September 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
325 ft
5 main spans
Daily traffic
850
1978 count
Owner
State
State Highway Agency

About this bridge

Mill ST over I-75 NB is a steel stringer/multi-beam or girder carrying Mill ST over I-75 NB in Otsego County, Michigan. It was built in 1962, so it is 63 years old, older than the Michigan average of 48.3 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 5 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

It carries about 850 vehicles a day, projected to reach 850 by 1979. The structure is 325 ft (99 m) long and 35 ft wide.

Location

Open in Google Maps
CarriesMill ST
CrossesI-75 NB
LocationNW Lts of Vanderbilt
RouteCity Street 0
CountyOtsego County
StateMichigan
Coordinates45.14922, -84.66963
Functional classRural Major Collector

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry6: Equal to present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating62.8 US tons
Inventory rating37.5 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans5
Design loadHS 20
Structure length325 ft (99 m)
Longest span90 ft (27.5 m)
Deck width35 ft (10.6 m)
Roadway width31 ft (9.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic850 (1978)
Projected traffic850 by 1979
Trucks—
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed—
TollOn a free road
National Highway SystemNo

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—
NavigationNot applicable (no waterway)

Frequently asked questions

When was Mill ST over I-75 NB built?

It was built in 1962, making it 63 years old in 2025.

What condition is Mill ST over I-75 NB in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in September 2024.

How much traffic does Mill ST over I-75 NB carry?

About 850 vehicles per day (1978 count).

How long is Mill ST over I-75 NB?

The structure is 325 ft (99 m) long with a longest span of 90 ft (27.5 m) and a deck 35 ft wide.

Who owns Mill ST over I-75 NB?

It is owned by the State Highway Agency.