US Bridges

NW 70th Ave over West Branch Bluff Creek

Fair

Harper County, Kansas · 1.2S 3.0E of Attica · Structure no. 000390729006822

Built
1945
80 years old, rebuilt 1995
Condition
Fair
inspected February 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
115 ft
5 main spans
Daily traffic
80
2021 count
Owner
County
County Highway Agency

About this bridge

NW 70th Ave over West Branch Bluff Creek is a steel continuous stringer/multi-beam or girder carrying NW 70th Ave over West Branch Bluff Creek in Harper County, Kansas. It was built in 1945 and reconstructed in 1995, so it is 80 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.

It carries about 80 vehicles a day, roughly 5% of them trucks, projected to reach 80 by 2043. The structure is 115 ft (35.1 m) long and 24 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

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CarriesNW 70th Ave
CrossesWest Branch Bluff Creek
Location1.2S 3.0E of Attica
RouteCounty Highway 0
CountyHarper County
StateKansas
Coordinates37.22192, -98.16622
Functional classRural Minor 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
Deck7 GoodSome minor problems.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionFebruary 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating23.6 US tons
Inventory rating14.1 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckCorrugated steel
Main spans5
Design loadUnknown
Structure length115 ft (35.1 m)
Longest span25 ft (7.5 m)
Deck width24 ft (7.3 m)
Roadway width24 ft (7.2 m)
Vertical clearance over deck100 ft (30.5 m)

Traffic and service

Average daily traffic80 (2021)
Projected traffic80 by 2043
Trucks5%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 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$140,000 (2023 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was NW 70th Ave over West Branch Bluff Creek built?

It was built in 1945, making it 80 years old in 2025. It was reconstructed in 1995.

What condition is NW 70th Ave over West Branch Bluff 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 February 2023.

How much traffic does NW 70th Ave over West Branch Bluff Creek carry?

About 80 vehicles per day (2021 count), of which roughly 5% are trucks.

How long is NW 70th Ave over West Branch Bluff Creek?

The structure is 115 ft (35.1 m) long with a longest span of 25 ft (7.5 m) and a deck 24 ft wide.

Who owns NW 70th Ave over West Branch Bluff Creek?

It is owned by the County Highway Agency.