US Bridges

Ia 5 NB over South River

Fair

Warren County, Iowa · 0.2 Mi. N of Jct. SR S31 · Structure no. 000000000050990

Built
1966
59 years old
Condition
Fair
inspected April 2022
Type
Girder and Floorbeam System
Steel Continuous
Length
391 ft
3 main spans
Daily traffic
4,300
2022 count
Owner
State
State Highway Agency

About this bridge

Ia 5 NB over South River is a steel continuous girder and floorbeam system carrying Ia 5 NB over South River in Warren County, Iowa. It was built in 1966, so it is 59 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 4,300 vehicles a day, roughly 10% of them trucks, projected to reach 4,300 by 2042. The structure is 391 ft (119.2 m) long and 36 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesIa 5 NB
CrossesSouth River
Location0.2 Mi. N of Jct. SR S31
RouteState Highway 5
CountyWarren County
StateIowa
Coordinates41.44376, -93.36092
Functional classRural Principal Arterial - Other

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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionApril 2022
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating44.9 US tons
Inventory rating27 US tons

Structure

Structure typeGirder and Floorbeam System
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length391 ft (119.2 m)
Longest span150 ft (45.7 m)
Deck width36 ft (11 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic4,300 (2022)
Projected traffic4,300 by 2042
Trucks10%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 km)
TollOn a free road
National Highway SystemYes

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 5 NB over South River built?

It was built in 1966, making it 59 years old in 2025.

What condition is Ia 5 NB over South 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 April 2022.

How much traffic does Ia 5 NB over South River carry?

About 4,300 vehicles per day (2022 count), of which roughly 10% are trucks.

How long is Ia 5 NB over South River?

The structure is 391 ft (119.2 m) long with a longest span of 150 ft (45.7 m) and a deck 36 ft wide.

Who owns Ia 5 NB over South River?

It is owned by the State Highway Agency.