US Bridges

SB I-380 over 5th Ave SW

Fair

Linn County, Iowa · 0.3 Mi. S of Ia 922 · Structure no. 000000000607110

Built
1975
50 years old
Condition
Fair
inspected October 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
269 ft
4 main spans
Daily traffic
26,000
2022 count
Owner
State
State Highway Agency

About this bridge

SB I-380 over 5th Ave SW is a steel continuous stringer/multi-beam or girder carrying SB I-380 over 5th Ave SW in Linn County, Iowa. It was built in 1975, so it is 50 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 26,000 vehicles a day, roughly 14% of them trucks, projected to reach 26,000 by 2044. The structure is 269 ft (82 m) long and 55 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

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CarriesSB I-380
Crosses5th Ave SW
Location0.3 Mi. S of Ia 922
RouteInterstate 380
CountyLinn County
StateIowa
Coordinates41.97136, -91.67403
Functional classUrban Principal Arterial - Interstate

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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Last inspectionOctober 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating55.3 US tons
Inventory rating32.4 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20
Structure length269 ft (82 m)
Longest span88 ft (26.8 m)
Deck width55 ft (16.9 m)
Roadway width52 ft (15.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic26,000 (2022)
Projected traffic26,000 by 2044
Trucks14%
Lanes on structure3
Traffic directionOne-way traffic
CarriesOverpass structure at an interchange
CrossesHighway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

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 SB I-380 over 5th Ave SW built?

It was built in 1975, making it 50 years old in 2025.

What condition is SB I-380 over 5th Ave SW 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 October 2024.

How much traffic does SB I-380 over 5th Ave SW carry?

About 26,000 vehicles per day (2022 count), of which roughly 14% are trucks.

How long is SB I-380 over 5th Ave SW?

The structure is 269 ft (82 m) long with a longest span of 88 ft (26.8 m) and a deck 55 ft wide.

Who owns SB I-380 over 5th Ave SW?

It is owned by the State Highway Agency.