US Bridges

Ia 146 over North Skunk River

Fair

Poweshiek County, Iowa · 2.7 Miles N of JCT US 63 · Structure no. 000000000045970

Built
1958
67 years old
Condition
Fair
inspected May 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
324 ft
3 main spans
Daily traffic
1,310
2023 count
Owner
State
State Highway Agency

About this bridge

Ia 146 over North Skunk River is a steel continuous stringer/multi-beam or girder carrying Ia 146 over North Skunk River in Poweshiek County, Iowa. It was built in 1958, so it is 67 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 1,310 vehicles a day, roughly 19% of them trucks, projected to reach 1,310 by 2043. The structure is 324 ft (98.8 m) long and 34 ft wide. If it were closed, the detour would be 11.8 mi (19 km).

Location

Open in Google Maps
CarriesIa 146
CrossesNorth Skunk River
Location2.7 Miles N of JCT US 63
RouteState Highway 146
CountyPoweshiek County
StateIowa
Coordinates41.50867, -92.65165
Functional classRural Minor Arterial

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMay 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating48.4 US tons
Inventory rating29 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadH 20
Structure length324 ft (98.8 m)
Longest span125 ft (38.1 m)
Deck width34 ft (10.3 m)
Roadway width28 ft (8.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,310 (2023)
Projected traffic1,310 by 2043
Trucks19%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed11.8 mi (19 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Ia 146 over North Skunk River built?

It was built in 1958, making it 67 years old in 2025.

What condition is Ia 146 over North Skunk River 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 2024.

How much traffic does Ia 146 over North Skunk River carry?

About 1,310 vehicles per day (2023 count), of which roughly 19% are trucks.

How long is Ia 146 over North Skunk River?

The structure is 324 ft (98.8 m) long with a longest span of 125 ft (38.1 m) and a deck 34 ft wide.

Who owns Ia 146 over North Skunk River?

It is owned by the State Highway Agency.