US Bridges

County Road 350 over Unknown Br

Fair

Carroll County, Missouri · S 7 T 51 N R 23 W · Structure no. 25079

Built
1900
125 years old, rebuilt 1988
Condition
Fair
inspected December 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
41 ft
1 main span
Daily traffic
55
2024 count
Owner
County
County Highway Agency

About this bridge

County Road 350 over Unknown Br is a steel stringer/multi-beam or girder carrying County Road 350 over Unknown Br in Carroll County, Missouri. It was built in 1900 and reconstructed in 1988, so it is 125 years old, older than the Missouri average of 45.1 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 55 vehicles a day, roughly 10% of them trucks, projected to reach 61 by 2044. The structure is 41 ft (12.5 m) long and 24 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesCounty Road 350
CrossesUnknown Br
LocationS 7 T 51 N R 23 W
RouteCounty Highway 618
CountyCarroll County
StateMissouri
Coordinates39.25328, -93.52345
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 protection7 GoodSome minor problems.
Last inspectionDecember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating50.6 US tons
Inventory rating30.8 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadOther
Structure length41 ft (12.5 m)
Longest span40 ft (12.2 m)
Deck width24 ft (7.3 m)
Roadway width23 ft (7.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic55 (2024)
Projected traffic61 by 2044
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty 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 County Road 350 over Unknown Br built?

It was built in 1900, making it 125 years old in 2025. It was reconstructed in 1988.

What condition is County Road 350 over Unknown Br 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 December 2023.

How much traffic does County Road 350 over Unknown Br carry?

About 55 vehicles per day (2024 count), of which roughly 10% are trucks.

How long is County Road 350 over Unknown Br?

The structure is 41 ft (12.5 m) long with a longest span of 40 ft (12.2 m) and a deck 24 ft wide.

Who owns County Road 350 over Unknown Br?

It is owned by the County Highway Agency.