US Bridges

120th St. Rs 51 over Marmaton River

FairPosted for load

Bourbon County, Kansas · 0.3S 0.2W of Redfield · Structure no. 000000000060110

Built
1959
66 years old
Condition
Fair
inspected May 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
323 ft
4 main spans
Daily traffic
209
2006 count
Owner
County
County Highway Agency

About this bridge

120th St. Rs 51 over Marmaton River is a steel continuous stringer/multi-beam or girder carrying 120th St. Rs 51 over Marmaton River in Bourbon County, Kansas. It was built in 1959, so it is 66 years old, older than the Kansas average of 52.8 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. Its operating status is: posted for load restriction.

It carries about 209 vehicles a day, roughly 10% of them trucks, projected to reach 20 by 2042. The structure is 323 ft (98.5 m) long and 28 ft wide. If it were closed, the detour would be 5 mi (8 km).

Location

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Carries120th St. Rs 51
CrossesMarmaton River
Location0.3S 0.2W of Redfield
RouteCounty Highway 51
CountyBourbon County
StateKansas
Coordinates37.83066, -94.88734
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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMay 2024
Inspection intervalevery 24 months
Operating statusPosted for load 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 adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating47.3 US tons
Inventory rating28 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans4
Design loadH 15
Structure length323 ft (98.5 m)
Longest span90 ft (27.4 m)
Deck width28 ft (8.6 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deck100 ft (30.5 m)

Traffic and service

Average daily traffic209 (2006)
Projected traffic20 by 2042
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 proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$849,000
NavigationNo navigation control on waterway

Frequently asked questions

When was 120th St. Rs 51 over Marmaton River built?

It was built in 1959, making it 66 years old in 2025.

What condition is 120th St. Rs 51 over Marmaton River 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 May 2024.

How much traffic does 120th St. Rs 51 over Marmaton River carry?

About 209 vehicles per day (2006 count), of which roughly 10% are trucks.

How long is 120th St. Rs 51 over Marmaton River?

The structure is 323 ft (98.5 m) long with a longest span of 90 ft (27.4 m) and a deck 28 ft wide.

Who owns 120th St. Rs 51 over Marmaton River?

It is owned by the County Highway Agency.