US Bridges

4th ST over Walnut Creek

Fair

Story County, Iowa · B35000505 · Structure no. 000000000502570

Built
1974
51 years old
Condition
Fair
inspected February 2023
Type
Culvert
Concrete Continuous
Length
40 ft
3 main spans
Daily traffic
278
2022 count
Owner
City
City or Municipal Highway Agency

About this bridge

4th ST over Walnut Creek is a concrete continuous culvert carrying 4th ST over Walnut Creek in Story County, Iowa. It was built in 1974, so it is 51 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 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 278 vehicles a day, roughly 11% of them trucks, projected to reach 278 by 2043. The structure is 40 ft (12.2 m) long. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
Carries4th ST
CrossesWalnut Creek
LocationB35000505
RouteCity Street 0
CountyStory County
StateIowa
Coordinates41.90058, -93.52793
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
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Culvert6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionFebruary 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating38 US tons
Inventory rating27 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckNot applicable
Main spans3
Design loadUnknown
Structure length40 ft (12.2 m)
Longest span12 ft (3.7 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic278 (2022)
Projected traffic278 by 2043
Trucks11%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCity or Municipal Highway Agency
Maintained byCity or Municipal Highway Agency
Historic statusPossibly eligible for the National Register; requires further investigation
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was 4th ST over Walnut Creek built?

It was built in 1974, making it 51 years old in 2025.

What condition is 4th ST over Walnut 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 4th ST over Walnut Creek carry?

About 278 vehicles per day (2022 count), of which roughly 11% are trucks.

How long is 4th ST over Walnut Creek?

The structure is 40 ft (12.2 m) long with a longest span of 12 ft (3.7 m).

Who owns 4th ST over Walnut Creek?

It is owned by the City or Municipal Highway Agency.