US Bridges

Ia 1 over Unnamed Stream

Good

Johnson County, Iowa · .4 MI S of Jct. SR F12/14 · Structure no. 000000000031851

Built
2014
11 years old
Condition
Good
inspected September 2024
Type
Culvert
Concrete
Length
25 ft
2 main spans
Daily traffic
6,000
2022 count
Owner
State
State Highway Agency

About this bridge

Ia 1 over Unnamed Stream is a concrete culvert carrying Ia 1 over Unnamed Stream in Johnson County, Iowa. It was built in 2014, so it is 11 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 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 6,000 vehicles a day, roughly 14% of them trucks, projected to reach 6,000 by 2044. The structure is 25 ft (7.6 m) long. If it were closed, the detour would be 26.1 mi (42 km).

Location

Open in Google Maps
CarriesIa 1
CrossesUnnamed Stream
Location.4 MI S of Jct. SR F12/14
RouteState Highway 1
CountyJohnson County
StateIowa
Coordinates41.82612, -91.49742
Functional classRural Principal Arterial - Other

Condition and inspection

Good

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

ComponentRatingMeaning
Channel and channel protection9 ExcellentNo problems noted.
Culvert8 Very GoodNo problems noted.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating57.5 US tons
Inventory rating44.3 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans2
Design loadHL 93
Structure length25 ft (7.6 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 traffic6,000 (2022)
Projected traffic6,000 by 2044
Trucks14%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed26.1 mi (42 km)
TollOn a free road
National Highway SystemYes

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 1 over Unnamed Stream built?

It was built in 2014, making it 11 years old in 2025.

What condition is Ia 1 over Unnamed Stream 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 September 2024.

How much traffic does Ia 1 over Unnamed Stream carry?

About 6,000 vehicles per day (2022 count), of which roughly 14% are trucks.

How long is Ia 1 over Unnamed Stream?

The structure is 25 ft (7.6 m) long with a longest span of 12 ft (3.7 m).

Who owns Ia 1 over Unnamed Stream?

It is owned by the State Highway Agency.