US Bridges

Ia 175 over Des Moines River

Fair

Webster County, Iowa · 1.8 Mi. E of JCT P70 · Structure no. 000000000052410

Built
1948
77 years old
Condition
Fair
inspected September 2022
Type
Girder and Floorbeam System
Steel Continuous
Length
699 ft
6 main spans
Daily traffic
730
2022 count
Owner
State
State Highway Agency

About this bridge

Ia 175 over Des Moines River is a steel continuous girder and floorbeam system carrying Ia 175 over Des Moines River in Webster County, Iowa. It was built in 1948, so it is 77 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 730 vehicles a day, roughly 11% of them trucks, projected to reach 730 by 2042. The structure is 699 ft (213.1 m) long and 31 ft wide. If it were closed, the detour would be 9.9 mi (16 km).

Location

Open in Google Maps
CarriesIa 175
CrossesDes Moines River
Location1.8 Mi. E of JCT P70
RouteState Highway 175
CountyWebster County
StateIowa
Coordinates42.25228, -93.9975
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
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.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionSeptember 2022
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
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
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating51 US tons
Inventory rating31 US tons

Structure

Structure typeGirder and Floorbeam System
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans6
Design loadH 20
Structure length699 ft (213.1 m)
Longest span128 ft (39 m)
Deck width31 ft (9.6 m)
Roadway width26 ft (7.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic730 (2022)
Projected traffic730 by 2042
Trucks11%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed9.9 mi (16 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—
NavigationNo navigation control on waterway

Frequently asked questions

When was Ia 175 over Des Moines River built?

It was built in 1948, making it 77 years old in 2025.

What condition is Ia 175 over Des Moines River 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 September 2022.

How much traffic does Ia 175 over Des Moines River carry?

About 730 vehicles per day (2022 count), of which roughly 11% are trucks.

How long is Ia 175 over Des Moines River?

The structure is 699 ft (213.1 m) long with a longest span of 128 ft (39 m) and a deck 31 ft wide.

Who owns Ia 175 over Des Moines River?

It is owned by the State Highway Agency.