US Bridges

SB Ia 14 over Iowa River

Fair

Marshall County, Iowa · 0.8 Mile South of SR E27 · Structure no. 000000000035431

Built
1987
38 years old
Condition
Fair
inspected October 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
478 ft
4 main spans
Daily traffic
2,950
2022 count
Owner
State
State Highway Agency

About this bridge

SB Ia 14 over Iowa River is a steel continuous stringer/multi-beam or girder carrying SB Ia 14 over Iowa River in Marshall County, Iowa. It was built in 1987, so it is 38 years old, younger 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 6 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 2,950 vehicles a day, roughly 6% of them trucks, projected to reach 2,950 by 2043. The structure is 478 ft (145.7 m) long and 35 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesSB Ia 14
CrossesIowa River
Location0.8 Mile South of SR E27
RouteState Highway 14
CountyMarshall County
StateIowa
Coordinates42.0669, -92.90829
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionOctober 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation7: Better than 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 rating93.1 US tons
Inventory rating55.8 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20
Structure length478 ft (145.7 m)
Longest span147 ft (44.8 m)
Deck width35 ft (10.7 m)
Roadway width32 ft (9.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,950 (2022)
Projected traffic2,950 by 2043
Trucks6%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 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 SB Ia 14 over Iowa River built?

It was built in 1987, making it 38 years old in 2025.

What condition is SB Ia 14 over Iowa 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 October 2023.

How much traffic does SB Ia 14 over Iowa River carry?

About 2,950 vehicles per day (2022 count), of which roughly 6% are trucks.

How long is SB Ia 14 over Iowa River?

The structure is 478 ft (145.7 m) long with a longest span of 147 ft (44.8 m) and a deck 35 ft wide.

Who owns SB Ia 14 over Iowa River?

It is owned by the State Highway Agency.