US Bridges

Mo 21 S over Logan CR

Fair

Ripley County, Missouri · S 1 T 23 N R 2 E · Structure no. 4628

Built
1922
103 years old
Condition
Fair
inspected January 2024
Type
Slab
Concrete
Length
22 ft
1 main span
Daily traffic
3,058
2024 count
Owner
State
State Highway Agency

About this bridge

Mo 21 S over Logan CR is a concrete slab carrying Mo 21 S over Logan CR in Ripley County, Missouri. It was built in 1922, so it is 103 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 3,058 vehicles a day, roughly 12% of them trucks, projected to reach 4,587 by 2044. The structure is 22 ft (6.7 m) long and 23 ft wide. If it were closed, the detour would be 28 mi (45 km).

Location

Open in Google Maps
CarriesMo 21 S
CrossesLogan CR
LocationS 1 T 23 N R 2 E
RouteState Highway 21
CountyRipley County
StateMissouri
Coordinates36.67888, -90.79209
Functional classRural Minor Arterial

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.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionJanuary 2024
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 geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating37.7 US tons
Inventory rating22.8 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadH 15
Structure length22 ft (6.7 m)
Longest span20 ft (6.1 m)
Deck width23 ft (7 m)
Roadway width23 ft (6.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic3,058 (2024)
Projected traffic4,587 by 2044
Trucks12%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed28 mi (45 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 proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$281,000 (2025 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Mo 21 S over Logan CR built?

It was built in 1922, making it 103 years old in 2025.

What condition is Mo 21 S over Logan 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 January 2024.

How much traffic does Mo 21 S over Logan CR carry?

About 3,058 vehicles per day (2024 count), of which roughly 12% are trucks.

How long is Mo 21 S over Logan CR?

The structure is 22 ft (6.7 m) long with a longest span of 20 ft (6.1 m) and a deck 23 ft wide.

Who owns Mo 21 S over Logan CR?

It is owned by the State Highway Agency.