US Bridges

US 18 over Little Cedar River

Fair

Chickasaw County, Iowa · 1.0 Mi. E. of SR T74 · Structure no. 000000000019570

Built
1966
59 years old
Condition
Fair
inspected August 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
306 ft
3 main spans
Daily traffic
2,120
2022 count
Owner
State
State Highway Agency

About this bridge

US 18 over Little Cedar River is a steel continuous stringer/multi-beam or girder carrying US 18 over Little Cedar River in Chickasaw County, Iowa. It was built in 1966, so it is 59 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 6 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 2,120 vehicles a day, roughly 16% of them trucks, projected to reach 2,120 by 2044. The structure is 306 ft (93.3 m) long and 36 ft wide. If it were closed, the detour would be 5 mi (8 km).

CarriesUS 18
CrossesLittle Cedar River
Location1.0 Mi. E. of SR T74
RouteU.S. Route 18
StateIowa
Coordinates43.06721, -92.54921
Functional classRural Principal Arterial - Other

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionAugust 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourCountermeasures installed to correct a previously existing problem
Structural evaluation6: Equal to present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating57.5 US tons
Inventory rating32.7 US tons

Structure

MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length306 ft (93.3 m)
Longest span117 ft (35.7 m)
Deck width36 ft (11 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,120 (2022)
Projected traffic2,120 by 2044
Trucks16%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed5 mi (8 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 US 18 over Little Cedar River built?

It was built in 1966, making it 59 years old in 2025.

What condition is US 18 over Little Cedar 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 August 2024.

How much traffic does US 18 over Little Cedar River carry?

About 2,120 vehicles per day (2022 count), of which roughly 16% are trucks.

How long is US 18 over Little Cedar River?

The structure is 306 ft (93.3 m) long with a longest span of 117 ft (35.7 m) and a deck 36 ft wide.

Who owns US 18 over Little Cedar River?

It is owned by the State Highway Agency.