US Bridges

County RD 306 over Rocky Br of Richla

Fair

Howard County, Missouri · S 9 T 50 N R 17 W · Structure no. 17131

Built
1983
42 years old, rebuilt 1999
Condition
Fair
inspected February 2024
Type
Girder and Floorbeam System
Steel
Length
35 ft
1 main span
Daily traffic
40
2024 count
Owner
County
County Highway Agency

About this bridge

County RD 306 over Rocky Br of Richla is a steel girder and floorbeam system carrying County RD 306 over Rocky Br of Richla in Howard County, Missouri. It was built in 1983 and reconstructed in 1999, so it is 42 years old, younger 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 5 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 40 vehicles a day, roughly 10% of them trucks, projected to reach 44 by 2044. The structure is 35 ft (10.7 m) long and 17 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesCounty RD 306
CrossesRocky Br of Richla
LocationS 9 T 50 N R 17 W
RouteCounty Highway 143
CountyHoward County
StateMissouri
Coordinates39.14313, -92.82571
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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
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 evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating71.4 US tons
Inventory rating42.7 US tons

Structure

Structure typeGirder and Floorbeam System
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadOther
Structure length35 ft (10.7 m)
Longest span32 ft (9.8 m)
Deck width17 ft (5.1 m)
Roadway width17 ft (5.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic40 (2024)
Projected traffic44 by 2044
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 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 proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$211,000 (2025 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was County RD 306 over Rocky Br of Richla built?

It was built in 1983, making it 42 years old in 2025. It was reconstructed in 1999.

What condition is County RD 306 over Rocky Br of Richla 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 February 2024.

How much traffic does County RD 306 over Rocky Br of Richla carry?

About 40 vehicles per day (2024 count), of which roughly 10% are trucks.

How long is County RD 306 over Rocky Br of Richla?

The structure is 35 ft (10.7 m) long with a longest span of 32 ft (9.8 m) and a deck 17 ft wide.

Who owns County RD 306 over Rocky Br of Richla?

It is owned by the County Highway Agency.