US Bridges

Mo 129 S over Blackbird CR

Fair

Putnam County, Missouri · S 30 T 66 N R 18 W · Structure no. 9563

Built
1947
78 years old
Condition
Fair
inspected December 2023
Type
Culvert
Concrete Continuous
Length
21 ft
2 main spans
Daily traffic
551
2024 count
Owner
State
State Highway Agency

About this bridge

Mo 129 S over Blackbird CR is a concrete continuous culvert carrying Mo 129 S over Blackbird CR in Putnam County, Missouri. It was built in 1947, so it is 78 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 551 vehicles a day, roughly 20% of them trucks, projected to reach 689 by 2044. The structure is 21 ft (6.4 m) long and 28 ft wide. If it were closed, the detour would be 14.3 mi (23 km).

Location

Open in Google Maps
CarriesMo 129 S
CrossesBlackbird CR
LocationS 30 T 66 N R 18 W
RouteState Highway 129
CountyPutnam County
StateMissouri
Coordinates40.50106, -92.96764
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
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Culvert6 SatisfactoryStructural elements show some minor deterioration.
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 adequacy6: Equal to present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating46.6 US tons
Inventory rating27.8 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckNot applicable
Main spans2
Design loadH 10
Structure length21 ft (6.4 m)
Longest span10 ft (3 m)
Deck width28 ft (8.5 m)
Roadway width26 ft (7.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic551 (2024)
Projected traffic689 by 2044
Trucks20%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed14.3 mi (23 km)
TollOn a free road
National Highway SystemNo

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 Mo 129 S over Blackbird CR built?

It was built in 1947, making it 78 years old in 2025.

What condition is Mo 129 S over Blackbird 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 December 2023.

How much traffic does Mo 129 S over Blackbird CR carry?

About 551 vehicles per day (2024 count), of which roughly 20% are trucks.

How long is Mo 129 S over Blackbird CR?

The structure is 21 ft (6.4 m) long with a longest span of 10 ft (3 m) and a deck 28 ft wide.

Who owns Mo 129 S over Blackbird CR?

It is owned by the State Highway Agency.