US Bridges

NW 158th Ave over Four Mile Creek Tributar

Fair

Polk County, Iowa · 081241001 · Structure no. 000000000282925

Built
1975
50 years old
Condition
Fair
inspected May 2023
Type
Culvert
Concrete Continuous
Length
22 ft
2 main spans
Daily traffic
264
2022 count
Owner
County
County Highway Agency

About this bridge

NW 158th Ave over Four Mile Creek Tributar is a concrete continuous culvert carrying NW 158th Ave over Four Mile Creek Tributar in Polk County, Iowa. It was built in 1975, so it is 50 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 264 vehicles a day, roughly 12% of them trucks, projected to reach 264 by 2042. The structure is 22 ft (6.7 m) long. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesNW 158th Ave
CrossesFour Mile Creek Tributar
Location081241001
RouteCounty Highway 0
CountyPolk County
StateIowa
Coordinates41.84941, -93.63739
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
Channel and channel protection7 GoodSome minor problems.
Culvert6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating34.4 US tons
Inventory rating20.6 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckNot applicable
Main spans2
Design loadHS 20
Structure length22 ft (6.7 m)
Longest span10 ft (3 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic264 (2022)
Projected traffic264 by 2042
Trucks12%
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

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—
NavigationNo navigation control on waterway

Frequently asked questions

When was NW 158th Ave over Four Mile Creek Tributar built?

It was built in 1975, making it 50 years old in 2025.

What condition is NW 158th Ave over Four Mile Creek Tributar 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 2023.

How much traffic does NW 158th Ave over Four Mile Creek Tributar carry?

About 264 vehicles per day (2022 count), of which roughly 12% are trucks.

How long is NW 158th Ave over Four Mile Creek Tributar?

The structure is 22 ft (6.7 m) long with a longest span of 10 ft (3 m).

Who owns NW 158th Ave over Four Mile Creek Tributar?

It is owned by the County Highway Agency.