US Bridges

Mo 143 S over Big CR

Fair

Iron County, Missouri · S 8 T 30 N R 4 E · Structure no. 8996

Built
1933
92 years old
Condition
Fair
inspected October 2023
Type
Tee Beam
Concrete
Length
238 ft
5 main spans
Daily traffic
590
2024 count
Owner
State
State Highway Agency

About this bridge

Mo 143 S over Big CR is a concrete tee beam carrying Mo 143 S over Big CR in Iron County, Missouri. It was built in 1933, so it is 92 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 5 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 590 vehicles a day, roughly 6% of them trucks, projected to reach 826 by 2044. The structure is 238 ft (72.5 m) long and 23 ft wide. If it were closed, the detour would be 49.1 mi (79 km).

Location

Open in Google Maps
CarriesMo 143 S
CrossesBig CR
LocationS 8 T 30 N R 4 E
RouteState Highway 143
CountyIron County
StateMissouri
Coordinates37.29277, -90.62893
Functional classRural Major Collector

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionOctober 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating41.7 US tons
Inventory rating22.8 US tons

Structure

Structure typeTee Beam
MaterialConcrete
DeckConcrete, cast-in-place
Main spans5
Design loadH 10
Structure length238 ft (72.5 m)
Longest span52 ft (16 m)
Deck width23 ft (7 m)
Roadway width20 ft (6.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic590 (2024)
Projected traffic826 by 2044
Trucks6%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed49.1 mi (79 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$2.4 million (2025 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Mo 143 S over Big CR built?

It was built in 1933, making it 92 years old in 2025.

What condition is Mo 143 S over Big CR 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 October 2023.

How much traffic does Mo 143 S over Big CR carry?

About 590 vehicles per day (2024 count), of which roughly 6% are trucks.

How long is Mo 143 S over Big CR?

The structure is 238 ft (72.5 m) long with a longest span of 52 ft (16 m) and a deck 23 ft wide.

Who owns Mo 143 S over Big CR?

It is owned by the State Highway Agency.