US Bridges

600th ST over Willow Creek

FairPosted for load

Cherokee County, Iowa · 090410601 · Structure no. 000000000107430

Built
1937
88 years old, rebuilt 2012
Condition
Fair
inspected August 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
85 ft
2 main spans
Daily traffic
11
2022 count
Owner
County
County Highway Agency

About this bridge

600th ST over Willow Creek is a steel stringer/multi-beam or girder carrying 600th ST over Willow Creek in Cherokee County, Iowa. It was built in 1937 and reconstructed in 2012, so it is 88 years old, older than the Iowa average of 45.5 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 other load-capacity restriction.

It carries about 11 vehicles a day, projected to reach 11 by 2043. The structure is 85 ft (25.9 m) long and 19 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
Carries600th ST
CrossesWillow Creek
Location090410601
RouteCounty Highway 0
CountyCherokee County
StateIowa
Coordinates42.64844, -95.73585
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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusPosted for other load-capacity restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating43.5 US tons
Inventory rating26.1 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckWood or timber
Main spans2
Design loadUnknown
Structure length85 ft (25.9 m)
Longest span42 ft (12.8 m)
Deck width19 ft (5.7 m)
Roadway width18 ft (5.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic11 (2022)
Projected traffic11 by 2043
Trucks0%
Lanes on structure2
Traffic directionOne-lane bridge for two-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 statusNot eligible for the National Register of Historic Places
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$950,000 (2023 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was 600th ST over Willow Creek built?

It was built in 1937, making it 88 years old in 2025. It was reconstructed in 2012.

What condition is 600th ST over Willow 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 2023.

How much traffic does 600th ST over Willow Creek carry?

About 11 vehicles per day (2022 count).

How long is 600th ST over Willow Creek?

The structure is 85 ft (25.9 m) long with a longest span of 42 ft (12.8 m) and a deck 19 ft wide.

Who owns 600th ST over Willow Creek?

It is owned by the County Highway Agency.