US Bridges

NB Ia 14 over Iowa River

Fair

Marshall County, Iowa · 0.8 Mile S of JCT SR E27 · Structure no. 000000000035420

Built
1968
57 years old
Condition
Fair
inspected February 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
481 ft
4 main spans
Daily traffic
2,950
2022 count
Owner
State
State Highway Agency

About this bridge

NB Ia 14 over Iowa River is a steel continuous stringer/multi-beam or girder carrying NB Ia 14 over Iowa River in Marshall County, Iowa. It was built in 1968, so it is 57 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 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 2044. The structure is 481 ft (146.6 m) long and 35 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesNB Ia 14
CrossesIowa River
Location0.8 Mile S of JCT SR E27
RouteState Highway 14
CountyMarshall County
StateIowa
Coordinates42.06559, -92.90807
Functional classUrban Other Principal 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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionFebruary 2024
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 alignment8: Equal to present desirable criteria
Operating rating75.4 US tons
Inventory rating45.2 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20
Structure length481 ft (146.6 m)
Longest span147 ft (44.8 m)
Deck width35 ft (10.8 m)
Roadway width32 ft (9.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,950 (2022)
Projected traffic2,950 by 2044
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 NB Ia 14 over Iowa River built?

It was built in 1968, making it 57 years old in 2025.

What condition is NB 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 February 2024.

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

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

How long is NB Ia 14 over Iowa River?

The structure is 481 ft (146.6 m) long with a longest span of 147 ft (44.8 m) and a deck 35 ft wide.

Who owns NB Ia 14 over Iowa River?

It is owned by the State Highway Agency.