US Bridges

NW 158th Ave over Big Creek

Good

Polk County, Iowa · 081250901 · Structure no. 000000000283121

Built
1990
35 years old
Condition
Good
inspected May 2023
Type
Slab
Concrete Continuous
Length
125 ft
3 main spans
Daily traffic
152
2022 count
Owner
County
County Highway Agency

About this bridge

NW 158th Ave over Big Creek is a concrete continuous slab carrying NW 158th Ave over Big Creek in Polk County, Iowa. It was built in 1990, so it is 35 years old, younger than the Iowa average of 45.5 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 152 vehicles a day, projected to reach 152 by 2042. The structure is 125 ft (38.1 m) long and 32 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesNW 158th Ave
CrossesBig Creek
Location081250901
RouteCounty Highway 0
CountyPolk County
StateIowa
Coordinates41.84947, -93.76725
Functional classRural Minor Collector

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure8 Very GoodNo problems noted.
Substructure7 GoodSome minor problems.
Channel and channel protection6 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 evaluation7: Better than present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating70.3 US tons
Inventory rating54.2 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length125 ft (38.1 m)
Longest span49 ft (14.9 m)
Deck width32 ft (9.8 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic152 (2022)
Projected traffic152 by 2042
Trucks0%
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 proposedOther structural work, including hydraulic replacements
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was NW 158th Ave over Big Creek built?

It was built in 1990, making it 35 years old in 2025.

What condition is NW 158th Ave over Big Creek in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in May 2023.

How much traffic does NW 158th Ave over Big Creek carry?

About 152 vehicles per day (2022 count).

How long is NW 158th Ave over Big Creek?

The structure is 125 ft (38.1 m) long with a longest span of 49 ft (14.9 m) and a deck 32 ft wide.

Who owns NW 158th Ave over Big Creek?

It is owned by the County Highway Agency.