US Bridges

Dyer Rock RD over Rock CR

Fair

Lafayette County, Missouri · S 14 T 49 N R 22 W · Structure no. 21267

Built
1920
105 years old, rebuilt 1980
Condition
Fair
inspected November 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
40 ft
1 main span
Daily traffic
20
2024 count
Owner
County
County Highway Agency

About this bridge

Dyer Rock RD over Rock CR is a steel stringer/multi-beam or girder carrying Dyer Rock RD over Rock CR in Lafayette County, Missouri. It was built in 1920 and reconstructed in 1980, so it is 105 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 20 vehicles a day, roughly 10% of them trucks, projected to reach 26 by 2044. The structure is 40 ft (12.2 m) long and 20 ft wide. If it were closed, the detour would be 5 mi (8 km).

Location

Open in Google Maps
CarriesDyer Rock RD
CrossesRock CR
LocationS 14 T 49 N R 22 W
RouteCounty Highway 298
CountyLafayette County
StateMissouri
Coordinates39.03868, -93.52219
Functional classRural Local

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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
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 inspectionNovember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating56.5 US tons
Inventory rating34.7 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadOther
Structure length40 ft (12.2 m)
Longest span38 ft (11.6 m)
Deck width20 ft (6.2 m)
Roadway width20 ft (6.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic20 (2024)
Projected traffic26 by 2044
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed5 mi (8 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 Dyer Rock RD over Rock CR built?

It was built in 1920, making it 105 years old in 2025. It was reconstructed in 1980.

What condition is Dyer Rock RD 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 Dyer Rock RD over Rock CR carry?

About 20 vehicles per day (2024 count), of which roughly 10% are trucks.

How long is Dyer Rock RD over Rock CR?

The structure is 40 ft (12.2 m) long with a longest span of 38 ft (11.6 m) and a deck 20 ft wide.

Who owns Dyer Rock RD over Rock CR?

It is owned by the County Highway Agency.