US Bridges

FM G-30 over I-80

Fair

Adair County, Iowa · At Jct. of SR G-30 · Structure no. 000000000012920

Built
1958
67 years old
Condition
Fair
inspected January 2024
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
254 ft
4 main spans
Daily traffic
1,654
2023 count
Owner
State
State Highway Agency

About this bridge

FM G-30 over I-80 is a prestressed concrete stringer/multi-beam or girder carrying FM G-30 over I-80 in Adair County, Iowa. It was built in 1958, 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 1,654 vehicles a day, roughly 9% of them trucks, projected to reach 1,654 by 2043. The structure is 254 ft (77.4 m) long and 36 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesFM G-30
CrossesI-80
LocationAt Jct. of SR G-30
RouteCounty Highway 0
CountyAdair County
StateIowa
Coordinates41.49288, -94.6626
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.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionJanuary 2024
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 geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment5: Somewhat better than minimum adequacy to tolerate being left in place as is
Operating rating88.3 US tons
Inventory rating32.4 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20
Structure length254 ft (77.4 m)
Longest span76 ft (23.2 m)
Deck width36 ft (11 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,654 (2023)
Projected traffic1,654 by 2043
Trucks9%
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 FM G-30 over I-80 built?

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

What condition is FM G-30 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 January 2024.

How much traffic does FM G-30 over I-80 carry?

About 1,654 vehicles per day (2023 count), of which roughly 9% are trucks.

How long is FM G-30 over I-80?

The structure is 254 ft (77.4 m) long with a longest span of 76 ft (23.2 m) and a deck 36 ft wide.

Who owns FM G-30 over I-80?

It is owned by the State Highway Agency.