US Bridges

Mo 6 E over Rock CR

Fair

Knox County, Missouri · S 30 T 62 N R 12 W · Structure no. 5328

Built
1929
96 years old
Condition
Fair
inspected November 2023
Type
Culvert
Concrete Continuous
Length
21 ft
2 main spans
Daily traffic
2,021
2024 count
Owner
State
State Highway Agency

About this bridge

Mo 6 E over Rock CR is a concrete continuous culvert carrying Mo 6 E over Rock CR in Knox County, Missouri. It was built in 1929, so it is 96 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 2,021 vehicles a day, roughly 33% of them trucks, projected to reach 3,840 by 2044. The structure is 21 ft (6.4 m) long and 37 ft wide. If it were closed, the detour would be 21.7 mi (35 km).

Location

Open in Google Maps
CarriesMo 6 E
CrossesRock CR
LocationS 30 T 62 N R 12 W
RouteState Highway 6
CountyKnox County
StateMissouri
Coordinates40.14671, -92.27092
Functional classRural Principal Arterial - Other

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 inspectionNovember 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 rating60.5 US tons
Inventory rating36.7 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckNot applicable
Main spans2
Design loadH 15
Structure length21 ft (6.4 m)
Longest span10 ft (3 m)
Deck width37 ft (11.3 m)
Roadway width35 ft (10.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,021 (2024)
Projected traffic3,840 by 2044
Trucks33%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed21.7 mi (35 km)
TollOn a free road
National Highway SystemYes

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 6 E over Rock CR built?

It was built in 1929, making it 96 years old in 2025.

What condition is Mo 6 E over Rock 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 November 2023.

How much traffic does Mo 6 E over Rock CR carry?

About 2,021 vehicles per day (2024 count), of which roughly 33% are trucks.

How long is Mo 6 E over Rock CR?

The structure is 21 ft (6.4 m) long with a longest span of 10 ft (3 m) and a deck 37 ft wide.

Who owns Mo 6 E over Rock CR?

It is owned by the State Highway Agency.