US Bridges

300 Road over Twelvemile Creek

FairPosted for load

Smith County, Kansas · 1.0N 4.3E of Portis · Structure no. 000920685303580

Built
1930
95 years old
Condition
Fair
inspected August 2024
Type
Girder and Floorbeam System
Steel
Length
52 ft
1 main span
Daily traffic
10
2020 count
Owner
County
County Highway Agency

About this bridge

300 Road over Twelvemile Creek is a steel girder and floorbeam system carrying 300 Road over Twelvemile Creek in Smith County, Kansas. It was built in 1930, so it is 95 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 5 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 10 vehicles a day, projected to reach 15 by 2044. The structure is 52 ft (15.9 m) long and 19 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
Carries300 Road
CrossesTwelvemile Creek
Location1.0N 4.3E of Portis
RouteCounty Highway 0
CountySmith County
StateKansas
Coordinates39.58205, -98.6142
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.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionAugust 2024
Inspection intervalevery 12 months
Operating statusPosted for load restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation2: Basically intolerable, requiring high priority of replacement
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy4: Meets minimum tolerable limits to be left in place as is
Approach roadway alignment6: Equal to present minimum criteria
Operating rating9.7 US tons
Inventory rating5.8 US tons

Structure

Structure typeGirder and Floorbeam System
MaterialSteel
DeckWood or timber
Main spans1 (+1 approach)
Design loadUnknown
Structure length52 ft (15.9 m)
Longest span39 ft (11.8 m)
Deck width19 ft (5.8 m)
Roadway width18 ft (5.6 m)
Vertical clearance over deck100 ft (30.5 m)

Traffic and service

Average daily traffic10 (2020)
Projected traffic15 by 2044
Trucks0%
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 statusPossibly eligible for the National Register; requires further investigation
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$300,000
NavigationNo navigation control on waterway

Frequently asked questions

When was 300 Road over Twelvemile Creek built?

It was built in 1930, making it 95 years old in 2025.

What condition is 300 Road over Twelvemile Creek 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 August 2024.

How much traffic does 300 Road over Twelvemile Creek carry?

About 10 vehicles per day (2020 count).

How long is 300 Road over Twelvemile Creek?

The structure is 52 ft (15.9 m) long with a longest span of 39 ft (11.8 m) and a deck 19 ft wide.

Who owns 300 Road over Twelvemile Creek?

It is owned by the County Highway Agency.