US Bridges

SR P28 over I-80

Fair

Adair County, Iowa · At Jct. SR P-28 · Structure no. 000000000013270

Built
1959
66 years old, rebuilt 1972
Condition
Fair
inspected February 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
210 ft
4 main spans
Daily traffic
4,502
2022 count
Owner
State
State Highway Agency

About this bridge

SR P28 over I-80 is a prestressed concrete stringer/multi-beam or girder carrying SR P28 over I-80 in Adair County, Iowa. It was built in 1959 and reconstructed in 1972, so it is 66 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 4,502 vehicles a day, roughly 11% of them trucks, projected to reach 4,502 by 2043. The structure is 210 ft (64 m) long and 34 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesSR P28
CrossesI-80
LocationAt Jct. SR P-28
RouteCity Street 0
CountyAdair County
StateIowa
Coordinates41.49274, -94.3185
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.
Substructure7 GoodSome minor problems.
Last inspectionFebruary 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 alignment5: Somewhat better than minimum adequacy to tolerate being left in place as is
Operating rating67.6 US tons
Inventory rating33 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans4
Design loadH 20
Structure length210 ft (64 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 traffic4,502 (2022)
Projected traffic4,502 by 2043
Trucks11%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesOverpass structure at an interchange
CrossesHighway
Detour if closed1.9 mi (3 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 P28 over I-80 built?

It was built in 1959, making it 66 years old in 2025. It was reconstructed in 1972.

What condition is SR P28 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 February 2023.

How much traffic does SR P28 over I-80 carry?

About 4,502 vehicles per day (2022 count), of which roughly 11% are trucks.

How long is SR P28 over I-80?

The structure is 210 ft (64 m) long with a longest span of 65 ft (19.8 m) and a deck 34 ft wide.

Who owns SR P28 over I-80?

It is owned by the State Highway Agency.