US Bridges

FM over Iowa River

Fair

Marshall County, Iowa · 084190205 · Structure no. 000000000243501

Built
1985
40 years old
Condition
Fair
inspected November 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
387 ft
4 main spans
Daily traffic
69
2022 count
Owner
County
County Highway Agency

About this bridge

FM over Iowa River is a prestressed concrete stringer/multi-beam or girder carrying FM over Iowa River in Marshall County, Iowa. It was built in 1985, so it is 40 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 69 vehicles a day, projected to reach 69 by 2043. The structure is 387 ft (118 m) long and 32 ft wide. If it were closed, the detour would be 8.7 mi (14 km).

Location

Open in Google Maps
CarriesFM
CrossesIowa River
Location084190205
RouteCounty Highway 0
CountyMarshall County
StateIowa
Coordinates42.11156, -93.02274
Functional classRural Minor Collector

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 inspectionNovember 2023
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 adequacy7: Better than present minimum criteria
Approach roadway alignment5: Somewhat better than minimum adequacy to tolerate being left in place as is
Operating rating52.4 US tons
Inventory rating31.4 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans4
Design loadH 20
Structure length387 ft (118 m)
Longest span97 ft (29.6 m)
Deck width32 ft (9.8 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic69 (2022)
Projected traffic69 by 2043
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed8.7 mi (14 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedOther structural work, including hydraulic replacements
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was FM over Iowa River built?

It was built in 1985, making it 40 years old in 2025.

What condition is FM 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 November 2023.

How much traffic does FM over Iowa River carry?

About 69 vehicles per day (2022 count).

How long is FM over Iowa River?

The structure is 387 ft (118 m) long with a longest span of 97 ft (29.6 m) and a deck 32 ft wide.

Who owns FM over Iowa River?

It is owned by the County Highway Agency.