US Bridges

320th Ave over Stream

Good

Clay County, Iowa · 097351102 · Structure no. 000000000117231

Built
2007
18 years old
Condition
Good
inspected March 2023
Type
Slab
Concrete
Length
24 ft
1 main span
Daily traffic
21
2022 count
Owner
County
County Highway Agency

About this bridge

320th Ave over Stream is a concrete slab carrying 320th Ave over Stream in Clay County, Iowa. It was built in 2007, so it is 18 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 21 vehicles a day, projected to reach 21 by 2043. The structure is 24 ft (7.3 m) long and 30 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
Carries320th Ave
CrossesStream
Location097351102
RouteCounty Highway 0
CountyClay County
StateIowa
Coordinates43.23085, -94.9568
Functional classRural Local

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.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMarch 2023
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating69.1 US tons
Inventory rating41.4 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length24 ft (7.3 m)
Longest span23 ft (7 m)
Deck width30 ft (9.1 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic21 (2022)
Projected traffic21 by 2043
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 statusPossibly eligible for the National Register; requires further investigation
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was 320th Ave over Stream built?

It was built in 2007, making it 18 years old in 2025.

What condition is 320th Ave over 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 March 2023.

How much traffic does 320th Ave over Stream carry?

About 21 vehicles per day (2022 count).

How long is 320th Ave over Stream?

The structure is 24 ft (7.3 m) long with a longest span of 23 ft (7 m) and a deck 30 ft wide.

Who owns 320th Ave over Stream?

It is owned by the County Highway Agency.