US Bridges

South CO Line RD over Flat River

Fair

Montcalm County, Michigan · 0.60 MI W of Berridge RD · Structure no. 000000000007498

Built
1996
29 years old
Condition
Fair
inspected March 2023
Type
Box Beam or Girders - Multiple
Prestressed Concrete
Length
120 ft
1 main span
Daily traffic
117
2003 count
Owner
County
County Highway Agency

About this bridge

South CO Line RD over Flat River is a prestressed concrete box beam or girders - multiple carrying South CO Line RD over Flat River in Montcalm County, Michigan. It was built in 1996, so it is 29 years old, younger 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 6 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 117 vehicles a day, projected to reach 133 by 2023. The structure is 120 ft (36.5 m) long and 33 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesSouth CO Line RD
CrossesFlat River
Location0.60 MI W of Berridge RD
RouteCounty Highway 0
CountyMontcalm County
StateMichigan
Coordinates43.11965, -85.22389
Functional classRural Local

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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionMarch 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to 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 rating110.1 US tons
Inventory rating69.7 US tons

Structure

Structure typeBox Beam or Girders - Multiple
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans1
Design loadHS 20
Structure length120 ft (36.5 m)
Longest span120 ft (36.5 m)
Deck width33 ft (10 m)
Roadway width31 ft (9.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic117 (2003)
Projected traffic133 by 2023
Trucks0%
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

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusListed on the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was South CO Line RD over Flat River built?

It was built in 1996, making it 29 years old in 2025.

What condition is South CO Line RD over Flat River 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 March 2023.

How much traffic does South CO Line RD over Flat River carry?

About 117 vehicles per day (2003 count).

How long is South CO Line RD over Flat River?

The structure is 120 ft (36.5 m) long with a longest span of 120 ft (36.5 m) and a deck 33 ft wide.

Who owns South CO Line RD over Flat River?

It is owned by the County Highway Agency.