US Bridges

SR N-54 over I-80

Fair

Adair County, Iowa · At Jct. SR N-54 · Structure no. 000000000013120

Built
1958
67 years old, rebuilt 1989
Condition
Fair
inspected March 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
222 ft
4 main spans
Daily traffic
2,158
2022 count
Owner
State
State Highway Agency

About this bridge

SR N-54 over I-80 is a prestressed concrete stringer/multi-beam or girder carrying SR N-54 over I-80 in Adair County, Iowa. It was built in 1958 and reconstructed in 1989, so it is 67 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.

It carries about 2,158 vehicles a day, roughly 12% of them trucks, projected to reach 2,158 by 2042. The structure is 222 ft (67.7 m) long and 34 ft wide. If it were closed, the detour would be 13 mi (21 km).

Location

Open in Google Maps
CarriesSR N-54
CrossesI-80
LocationAt Jct. SR N-54
RouteCity Street 0
CountyAdair County
StateIowa
Coordinates41.4929, -94.64349
Functional classRural Major 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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMarch 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Approach roadway alignment6: Equal to present minimum criteria
Operating rating48.8 US tons
Inventory rating36.3 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans4
Design loadH 20
Structure length222 ft (67.7 m)
Longest span65 ft (19.8 m)
Deck width34 ft (10.4 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,158 (2022)
Projected traffic2,158 by 2042
Trucks12%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesOverpass structure at an interchange
CrossesHighway
Detour if closed13 mi (21 km)
TollOn a free road
National Highway SystemNo

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—
NavigationNot applicable (no waterway)

Frequently asked questions

When was SR N-54 over I-80 built?

It was built in 1958, making it 67 years old in 2025. It was reconstructed in 1989.

What condition is SR N-54 over I-80 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 March 2023.

How much traffic does SR N-54 over I-80 carry?

About 2,158 vehicles per day (2022 count), of which roughly 12% are trucks.

How long is SR N-54 over I-80?

The structure is 222 ft (67.7 m) long with a longest span of 65 ft (19.8 m) and a deck 34 ft wide.

Who owns SR N-54 over I-80?

It is owned by the State Highway Agency.