US Bridges

FM 580th St. over Little Sioux River

Fair

Cherokee County, Iowa · 091402801 · Structure no. 000000000108171

Built
1981
44 years old
Condition
Fair
inspected July 2023
Type
Girder and Floorbeam System
Steel Continuous
Length
415 ft
4 main spans
Daily traffic
350
2022 count
Owner
County
County Highway Agency

About this bridge

FM 580th St. over Little Sioux River is a steel continuous girder and floorbeam system carrying FM 580th St. over Little Sioux River in Cherokee County, Iowa. It was built in 1981, so it is 44 years old, younger 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.

It carries about 350 vehicles a day, roughly 20% of them trucks, projected to reach 350 by 2043. The structure is 415 ft (126.5 m) long and 32 ft wide. If it were closed, the detour would be 11.2 mi (18 km).

Location

Open in Google Maps
CarriesFM 580th St.
CrossesLittle Sioux River
Location091402801
RouteCounty Highway 0
CountyCherokee County
StateIowa
Coordinates42.67716, -95.57054
Functional classRural Minor Collector

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.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
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 evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating64.4 US tons
Inventory rating38.6 US tons

Structure

Structure typeGirder and Floorbeam System
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans4
Design loadH 20
Structure length415 ft (126.5 m)
Longest span115 ft (35.1 m)
Deck width32 ft (9.8 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic350 (2022)
Projected traffic350 by 2043
Trucks20%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed11.2 mi (18 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 proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$4.5 million (2024 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was FM 580th St. over Little Sioux River built?

It was built in 1981, making it 44 years old in 2025.

What condition is FM 580th St. over Little Sioux 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 July 2023.

How much traffic does FM 580th St. over Little Sioux River carry?

About 350 vehicles per day (2022 count), of which roughly 20% are trucks.

How long is FM 580th St. over Little Sioux River?

The structure is 415 ft (126.5 m) long with a longest span of 115 ft (35.1 m) and a deck 32 ft wide.

Who owns FM 580th St. over Little Sioux River?

It is owned by the County Highway Agency.