US Bridges

County RD 166 over Rock CR

Good

Atchison County, Missouri · S 22 T 65 N R 41 W · Structure no. 17904

Built
1989
36 years old
Condition
Good
inspected February 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
100 ft
2 main spans
Daily traffic
35
2024 count
Owner
County
County Highway Agency

About this bridge

County RD 166 over Rock CR is a steel stringer/multi-beam or girder carrying County RD 166 over Rock CR in Atchison County, Missouri. It was built in 1989, so it is 36 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 35 vehicles a day, roughly 10% of them trucks, projected to reach 40 by 2044. The structure is 100 ft (30.5 m) long and 25 ft wide. If it were closed, the detour would be 0.6 mi (1 km).

Location

Open in Google Maps
CarriesCounty RD 166
CrossesRock CR
LocationS 22 T 65 N R 41 W
RouteCounty Highway 166
CountyAtchison County
StateMissouri
Coordinates40.43877, -95.50442
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
Deck8 Very GoodNo problems noted.
Superstructure8 Very GoodNo problems noted.
Substructure7 GoodSome minor problems.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionFebruary 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating75.4 US tons
Inventory rating55.6 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans2
Design loadOther
Structure length100 ft (30.5 m)
Longest span59 ft (18 m)
Deck width25 ft (7.6 m)
Roadway width22 ft (6.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic35 (2024)
Projected traffic40 by 2044
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed0.6 mi (1 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 County RD 166 over Rock CR built?

It was built in 1989, making it 36 years old in 2025.

What condition is County RD 166 over 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 February 2024.

How much traffic does County RD 166 over Rock CR carry?

About 35 vehicles per day (2024 count), of which roughly 10% are trucks.

How long is County RD 166 over Rock CR?

The structure is 100 ft (30.5 m) long with a longest span of 59 ft (18 m) and a deck 25 ft wide.

Who owns County RD 166 over Rock CR?

It is owned by the County Highway Agency.