US Bridges

NW 166th Ave over Big Creek Tributary

Fair

Polk County, Iowa · 081250301 · Structure no. 000000000363615

Built
1992
33 years old
Condition
Fair
inspected May 2023
Type
Culvert
Steel
Length
25 ft
3 main spans
Daily traffic
61
2022 count
Owner
County
County Highway Agency

About this bridge

NW 166th Ave over Big Creek Tributary is a steel culvert carrying NW 166th Ave over Big Creek Tributary in Polk County, Iowa. It was built in 1992, so it is 33 years old, younger 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 61 vehicles a day, projected to reach 61 by 2042. The structure is 25 ft (7.6 m) long. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesNW 166th Ave
CrossesBig Creek Tributary
Location081250301
RouteCounty Highway 0
CountyPolk County
StateIowa
Coordinates41.86341, -93.75266
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
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
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 evaluation6: Equal to present minimum criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating48.6 US tons
Inventory rating36 US tons

Structure

Structure typeCulvert
MaterialSteel
DeckNot applicable
Main spans3
Design loadHS 20
Structure length25 ft (7.6 m)
Longest span7 ft (2.1 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic61 (2022)
Projected traffic61 by 2042
Trucks0%
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 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 166th Ave over Big Creek Tributary built?

It was built in 1992, making it 33 years old in 2025.

What condition is NW 166th Ave over Big Creek Tributary 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 166th Ave over Big Creek Tributary carry?

About 61 vehicles per day (2022 count).

How long is NW 166th Ave over Big Creek Tributary?

The structure is 25 ft (7.6 m) long with a longest span of 7 ft (2.1 m).

Who owns NW 166th Ave over Big Creek Tributary?

It is owned by the County Highway Agency.