US Bridges

Ia 173 over I-80

Fair

Cass County, Iowa · At Jct. I-80 · Structure no. 000000000018010

Built
1964
61 years old
Condition
Fair
inspected February 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
235 ft
4 main spans
Daily traffic
1,430
2022 count
Owner
State
State Highway Agency

About this bridge

Ia 173 over I-80 is a prestressed concrete stringer/multi-beam or girder carrying Ia 173 over I-80 in Cass County, Iowa. It was built in 1964, so it is 61 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 1,430 vehicles a day, roughly 8% of them trucks, projected to reach 1,430 by 2043. The structure is 235 ft (71.6 m) long and 36 ft wide. If it were closed, the detour would be 8.1 mi (13 km).

Location

Open in Google Maps
CarriesIa 173
CrossesI-80
LocationAt Jct. I-80
RouteState Highway 173
CountyCass County
StateIowa
Coordinates41.49652, -95.06013
Functional classRural Minor Arterial

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
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 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 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 rating99.8 US tons
Inventory rating62.1 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20
Structure length235 ft (71.6 m)
Longest span73 ft (22.3 m)
Deck width36 ft (11 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,430 (2022)
Projected traffic1,430 by 2043
Trucks8%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesOverpass structure at an interchange
CrossesHighway
Detour if closed8.1 mi (13 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 Ia 173 over I-80 built?

It was built in 1964, making it 61 years old in 2025.

What condition is Ia 173 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 Ia 173 over I-80 carry?

About 1,430 vehicles per day (2022 count), of which roughly 8% are trucks.

How long is Ia 173 over I-80?

The structure is 235 ft (71.6 m) long with a longest span of 73 ft (22.3 m) and a deck 36 ft wide.

Who owns Ia 173 over I-80?

It is owned by the State Highway Agency.