US Bridges

SB I-35 over South River

Good

Warren County, Iowa · 1.7 Mi. N of Jct. SR G-26 · Structure no. 000000000051231

Built
2012
13 years old
Condition
Good
inspected October 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
243 ft
3 main spans
Daily traffic
10,150
2023 count
Owner
State
State Highway Agency

About this bridge

SB I-35 over South River is a steel continuous stringer/multi-beam or girder carrying SB I-35 over South River in Warren County, Iowa. It was built in 2012, so it is 13 years old, younger than the Iowa average of 45.5 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 10,150 vehicles a day, roughly 30% of them trucks, projected to reach 10,150 by 2043. The structure is 243 ft (74.2 m) long and 43 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesSB I-35
CrossesSouth River
Location1.7 Mi. N of Jct. SR G-26
RouteInterstate 35
StateIowa
Coordinates41.20098, -93.78699
Functional classRural Principal Arterial - Interstate

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure8 Very GoodNo problems noted.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionOctober 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating47.5 US tons
Inventory rating35.7 US tons

Structure

MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHL 93
Structure length243 ft (74.2 m)
Longest span96 ft (29.3 m)
Deck width43 ft (13.2 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic10,150 (2023)
Projected traffic10,150 by 2043
Trucks30%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
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—
NavigationNo navigation control on waterway

Frequently asked questions

When was SB I-35 over South River built?

It was built in 2012, making it 13 years old in 2025.

What condition is SB I-35 over South River in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in October 2024.

How much traffic does SB I-35 over South River carry?

About 10,150 vehicles per day (2023 count), of which roughly 30% are trucks.

How long is SB I-35 over South River?

The structure is 243 ft (74.2 m) long with a longest span of 96 ft (29.3 m) and a deck 43 ft wide.

Who owns SB I-35 over South River?

It is owned by the State Highway Agency.