US Bridges

M-46|W Monroe RD over W Br Pine River

Good

Gratiot County, Michigan · 2.1 MI W of US 27 · Structure no. 000000000003128

Built
2006
19 years old
Condition
Good
inspected December 2024
Type
Culvert
Concrete
Length
28 ft
1 main span
Daily traffic
6,570
2007 count
Owner
State
State Highway Agency

About this bridge

M-46|W Monroe RD over W Br Pine River is a concrete culvert carrying M-46|W Monroe RD over W Br Pine River in Gratiot County, Michigan. It was built in 2006, so it is 19 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 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 6,570 vehicles a day, roughly 8% of them trucks, projected to reach 11,363 by 2018. The structure is 28 ft (8.6 m) long. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesM-46|W Monroe RD
CrossesW Br Pine River
Location2.1 MI W of US 27
RouteState Highway 46
CountyGratiot County
StateMichigan
Coordinates43.40813, -84.70259
Functional classRural Principal Arterial - Other

Condition and inspection

Good

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

ComponentRatingMeaning
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Culvert8 Very GoodNo problems noted.
Last inspectionDecember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation8: Equal to present desirable criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating72.5 US tons
Inventory rating43.2 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans1
Design loadHS 20 + Mod
Structure length28 ft (8.6 m)
Longest span28 ft (8.6 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic6,570 (2007)
Projected traffic11,363 by 2018
Trucks8%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 km)
TollOn a free road
National Highway SystemYes

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-46|W Monroe RD over W Br Pine River built?

It was built in 2006, making it 19 years old in 2025.

What condition is M-46|W Monroe RD over W Br Pine 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 December 2024.

How much traffic does M-46|W Monroe RD over W Br Pine River carry?

About 6,570 vehicles per day (2007 count), of which roughly 8% are trucks.

How long is M-46|W Monroe RD over W Br Pine River?

The structure is 28 ft (8.6 m) long with a longest span of 28 ft (8.6 m).

Who owns M-46|W Monroe RD over W Br Pine River?

It is owned by the State Highway Agency.