US Bridges

320th Street over Stream

Good

Pottawattamie County, Iowa · 075410902 · Structure no. 000000000286142

Built
2015
10 years old
Condition
Good
inspected July 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
102 ft
1 main span
Daily traffic
20
2022 count
Owner
County
County Highway Agency

About this bridge

320th Street over Stream is a steel stringer/multi-beam or girder carrying 320th Street over Stream in Pottawattamie County, Iowa. It was built in 2015, so it is 10 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 20 vehicles a day, projected to reach 20 by 2043. The structure is 102 ft (31.1 m) long and 24 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
Carries320th Street
CrossesStream
Location075410902
RouteCounty Highway 0
CountyPottawattamie County
StateIowa
Coordinates41.30733, -95.57503
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
Deck8 Very GoodNo problems noted.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJuly 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating59.3 US tons
Inventory rating45.7 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadHL 93
Structure length102 ft (31.1 m)
Longest span99 ft (30.2 m)
Deck width24 ft (7.3 m)
Roadway width23 ft (7.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic20 (2022)
Projected traffic20 by 2043
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 proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was 320th Street over Stream built?

It was built in 2015, making it 10 years old in 2025.

What condition is 320th Street 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 July 2023.

How much traffic does 320th Street over Stream carry?

About 20 vehicles per day (2022 count).

How long is 320th Street over Stream?

The structure is 102 ft (31.1 m) long with a longest span of 99 ft (30.2 m) and a deck 24 ft wide.

Who owns 320th Street over Stream?

It is owned by the County Highway Agency.