US Bridges

185th Trail over Big Rock CR

Good

Worth County, Missouri · S 8 T 65 N R 30 W · Structure no. 17971

Built
1990
35 years old
Condition
Good
inspected December 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
80 ft
1 main span
Daily traffic
30
2024 count
Owner
County
County Highway Agency

About this bridge

185th Trail over Big Rock CR is a steel stringer/multi-beam or girder carrying 185th Trail over Big Rock CR in Worth County, Missouri. It was built in 1990, so it is 35 years old, younger than the Missouri average of 45.1 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 30 vehicles a day, roughly 10% of them trucks, projected to reach 35 by 2044. The structure is 80 ft (24.4 m) long and 18 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

Carries185th Trail
CrossesBig Rock CR
LocationS 8 T 65 N R 30 W
RouteCounty Highway 168
Coordinates40.45173, -94.29904
Functional classRural Local

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionDecember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating61.5 US tons
Inventory rating34.7 US tons

Structure

MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadH 10
Structure length80 ft (24.4 m)
Longest span71 ft (21.6 m)
Deck width18 ft (5.5 m)
Roadway width18 ft (5.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic30 (2024)
Projected traffic35 by 2044
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.2 mi (10 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 185th Trail over Big Rock CR built?

It was built in 1990, making it 35 years old in 2025.

What condition is 185th Trail over Big Rock CR in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in December 2024.

How much traffic does 185th Trail over Big Rock CR carry?

About 30 vehicles per day (2024 count), of which roughly 10% are trucks.

How long is 185th Trail over Big Rock CR?

The structure is 80 ft (24.4 m) long with a longest span of 71 ft (21.6 m) and a deck 18 ft wide.

Who owns 185th Trail over Big Rock CR?

It is owned by the County Highway Agency.