US Bridges

M-64 over Pine River

Poor

Ontonagon County, Michigan · 4.0 MI NE of M-107 · Structure no. 000000000008469

Built
1968
57 years old
Condition
Poor
inspected August 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
54 ft
1 main span
Daily traffic
1,032
2007 count
Owner
State
State Highway Agency

About this bridge

M-64 over Pine River is a steel stringer/multi-beam or girder carrying M-64 over Pine River in Ontonagon County, Michigan. It was built in 1968, so it is 57 years old, older than the Michigan average of 48.3 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

It carries about 1,032 vehicles a day, roughly 11% of them trucks, projected to reach 1,149 by 2018. The structure is 54 ft (16.5 m) long and 46 ft wide. If it were closed, the detour would be 24.9 mi (40 km).

Location

Open in Google Maps
CarriesM-64
CrossesPine River
Location4.0 MI NE of M-107
RouteState Highway 64
CountyOntonagon County
StateMichigan
Coordinates46.83654, -89.48897
Functional classRural Minor Arterial

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Deck4 PoorAdvanced section loss, deterioration, spalling or scour.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionAugust 2024
Inspection intervalevery 12 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating79.7 US tons
Inventory rating47.8 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadH 20
Structure length54 ft (16.5 m)
Longest span52 ft (16 m)
Deck width46 ft (14.1 m)
Roadway width43 ft (13 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,032 (2007)
Projected traffic1,149 by 2018
Trucks11%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed24.9 mi (40 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-64 over Pine River built?

It was built in 1968, making it 57 years old in 2025.

What condition is M-64 over Pine River in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in August 2024.

How much traffic does M-64 over Pine River carry?

About 1,032 vehicles per day (2007 count), of which roughly 11% are trucks.

How long is M-64 over Pine River?

The structure is 54 ft (16.5 m) long with a longest span of 52 ft (16 m) and a deck 46 ft wide.

Who owns M-64 over Pine River?

It is owned by the State Highway Agency.