US Bridges

M-66 over Middle Branch River

Good

Osceola County, Michigan · 2.2 MI N of M-61 · Structure no. 000000000008593

Built
1995
30 years old
Condition
Good
inspected September 2024
Type
Box Beam or Girders - Multiple
Prestressed Concrete
Length
80 ft
1 main span
Daily traffic
1,685
2007 count
Owner
State
State Highway Agency

About this bridge

M-66 over Middle Branch River is a prestressed concrete box beam or girders - multiple carrying M-66 over Middle Branch River in Osceola County, Michigan. It was built in 1995, so it is 30 years old, younger 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 1,685 vehicles a day, roughly 9% of them trucks, projected to reach 2,626 by 2018. The structure is 80 ft (24.3 m) long and 47 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesM-66
CrossesMiddle Branch River
Location2.2 MI N of M-61
RouteState Highway 66
CountyOsceola County
StateMichigan
Coordinates44.07693, -85.14734
Functional classRural Minor Arterial

Condition and inspection

Good

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

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourCountermeasures installed to correct a previously existing problem
Structural evaluation7: Better than present minimum criteria
Deck geometry8: Equal to present desirable criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment5: Somewhat better than minimum adequacy to tolerate being left in place as is
Operating rating88.6 US tons
Inventory rating44.6 US tons

Structure

Structure typeBox Beam or Girders - Multiple
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 25 or greater
Structure length80 ft (24.3 m)
Longest span76 ft (23.1 m)
Deck width47 ft (14.4 m)
Roadway width44 ft (13.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,685 (2007)
Projected traffic2,626 by 2018
Trucks9%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 km)
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—
NavigationNo navigation control on waterway

Frequently asked questions

When was M-66 over Middle Branch River built?

It was built in 1995, making it 30 years old in 2025.

What condition is M-66 over Middle Branch River 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 September 2024.

How much traffic does M-66 over Middle Branch River carry?

About 1,685 vehicles per day (2007 count), of which roughly 9% are trucks.

How long is M-66 over Middle Branch River?

The structure is 80 ft (24.3 m) long with a longest span of 76 ft (23.1 m) and a deck 47 ft wide.

Who owns M-66 over Middle Branch River?

It is owned by the State Highway Agency.