US Bridges

S Byrnville RD over Big Rvr

Fair

Jefferson County, Missouri · S 12 T 42 N R 3 E · Structure no. 17620

Built
1910
115 years old, rebuilt 1983
Condition
Fair
inspected February 2025
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
264 ft
3 main spans
Daily traffic
1,354
2023 count
Owner
County
County Highway Agency

About this bridge

S Byrnville RD over Big Rvr is a steel continuous stringer/multi-beam or girder carrying S Byrnville RD over Big Rvr in Jefferson County, Missouri. It was built in 1910 and reconstructed in 1983, so it is 115 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 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 1,354 vehicles a day, roughly 2% of them trucks, projected to reach 2,708 by 2043. The structure is 264 ft (80.5 m) long and 30 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesS Byrnville RD
CrossesBig Rvr
LocationS 12 T 42 N R 3 E
RouteCounty Highway 134
CountyJefferson County
StateMissouri
Coordinates38.39253, -90.63722
Functional classRural Major Collector

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 protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionFebruary 2025
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourCountermeasures installed to correct a previously existing problem
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy4: Meets minimum tolerable limits to be left in place as is
Approach roadway alignment4: Meets minimum tolerable limits to be left in place as is
Operating rating46.6 US tons
Inventory rating23.8 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadH 15
Structure length264 ft (80.5 m)
Longest span120 ft (36.6 m)
Deck width30 ft (9.1 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,354 (2023)
Projected traffic2,708 by 2043
Trucks2%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was S Byrnville RD over Big Rvr built?

It was built in 1910, making it 115 years old in 2025. It was reconstructed in 1983.

What condition is S Byrnville RD over Big Rvr 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 2025.

How much traffic does S Byrnville RD over Big Rvr carry?

About 1,354 vehicles per day (2023 count), of which roughly 2% are trucks.

How long is S Byrnville RD over Big Rvr?

The structure is 264 ft (80.5 m) long with a longest span of 120 ft (36.6 m) and a deck 30 ft wide.

Who owns S Byrnville RD over Big Rvr?

It is owned by the County Highway Agency.