US Bridges

Ia 3 over Big Sioux Overflow

Fair

Plymouth County, Iowa · 1.3 Mi. W of Jct. Ia 12 · Structure no. 000000000039660

Built
1962
63 years old
Condition
Fair
inspected April 2024
Type
Slab
Concrete Continuous
Length
102 ft
3 main spans
Daily traffic
1,570
2022 count
Owner
State
State Highway Agency

About this bridge

Ia 3 over Big Sioux Overflow is a concrete continuous slab carrying Ia 3 over Big Sioux Overflow in Plymouth County, Iowa. It was built in 1962, so it is 63 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 1,570 vehicles a day, roughly 29% of them trucks, projected to reach 1,570 by 2044. The structure is 102 ft (31.1 m) long and 36 ft wide. If it were closed, the detour would be 9.9 mi (16 km).

Location

Open in Google Maps
CarriesIa 3
CrossesBig Sioux Overflow
Location1.3 Mi. W of Jct. Ia 12
RouteState Highway 3
CountyPlymouth County
StateIowa
Coordinates42.76182, -96.62891
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 protection8 Very GoodNo problems noted.
Last inspectionApril 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
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 adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating61.6 US tons
Inventory rating37 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length102 ft (31.1 m)
Longest span39 ft (11.9 m)
Deck width36 ft (11 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,570 (2022)
Projected traffic1,570 by 2044
Trucks29%
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 3 over Big Sioux Overflow built?

It was built in 1962, making it 63 years old in 2025.

What condition is Ia 3 over Big Sioux Overflow 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 April 2024.

How much traffic does Ia 3 over Big Sioux Overflow carry?

About 1,570 vehicles per day (2022 count), of which roughly 29% are trucks.

How long is Ia 3 over Big Sioux Overflow?

The structure is 102 ft (31.1 m) long with a longest span of 39 ft (11.9 m) and a deck 36 ft wide.

Who owns Ia 3 over Big Sioux Overflow?

It is owned by the State Highway Agency.