US Bridges

320th over Creek

FairPosted for load

Cerro Gordo County, Iowa · 097201601 · Structure no. 000000000106680

Built
1955
70 years old
Condition
Fair
inspected January 2024
Type
Truss - Thru
Steel
Length
70 ft
1 main span
Daily traffic
59
2022 count
Owner
County
County Highway Agency

About this bridge

320th over Creek is a steel truss - thru carrying 320th over Creek in Cerro Gordo County, Iowa. It was built in 1955, so it is 70 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 5 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. Its operating status is: posted for load restriction.

It carries about 59 vehicles a day, projected to reach 59 by 2044. The structure is 70 ft (21.3 m) long and 21 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
Carries320th
CrossesCreek
Location097201601
RouteCounty Highway 0
CountyCerro Gordo County
StateIowa
Coordinates43.22747, -93.21135
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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJanuary 2024
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating34.7 US tons
Inventory rating21.8 US tons

Structure

Structure typeTruss - Thru
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadH 15
Structure length70 ft (21.3 m)
Longest span70 ft (21.3 m)
Deck width21 ft (6.5 m)
Roadway width20 ft (6.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic59 (2022)
Projected traffic59 by 2044
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 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 proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was 320th over Creek built?

It was built in 1955, making it 70 years old in 2025.

What condition is 320th over Creek 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 January 2024.

How much traffic does 320th over Creek carry?

About 59 vehicles per day (2022 count).

How long is 320th over Creek?

The structure is 70 ft (21.3 m) long with a longest span of 70 ft (21.3 m) and a deck 21 ft wide.

Who owns 320th over Creek?

It is owned by the County Highway Agency.