US Bridges

Irr-Fm over Iowa River Overflow

Fair

Tama County, Iowa · 083152907 · Structure no. 000000000318220

Built
1972
53 years old, rebuilt 1985
Condition
Fair
inspected October 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
68 ft
2 main spans
Daily traffic
619
2022 count
Owner
County
County Highway Agency

About this bridge

Irr-Fm over Iowa River Overflow is a steel stringer/multi-beam or girder carrying Irr-Fm over Iowa River Overflow in Tama County, Iowa. It was built in 1972 and reconstructed in 1985, so it is 53 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 619 vehicles a day, roughly 13% of them trucks, projected to reach 619 by 2044. The structure is 68 ft (20.7 m) long and 32 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

CarriesIrr-Fm
CrossesIowa River Overflow
Location083152907
RouteCounty Highway 0
StateIowa
Coordinates41.96404, -92.62382
Functional classRural Major 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.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionOctober 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating53.5 US tons
Inventory rating35.4 US tons

Structure

MaterialSteel
DeckConcrete, cast-in-place
Main spans2
Design loadH 20
Structure length68 ft (20.7 m)
Longest span33 ft (10.1 m)
Deck width32 ft (9.8 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic619 (2022)
Projected traffic619 by 2044
Trucks13%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusPossibly eligible for the National Register; requires further investigation
Work proposedOther structural work, including hydraulic replacements
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Irr-Fm over Iowa River Overflow built?

It was built in 1972, making it 53 years old in 2025. It was reconstructed in 1985.

What condition is Irr-Fm over Iowa River Overflow 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 2024.

How much traffic does Irr-Fm over Iowa River Overflow carry?

About 619 vehicles per day (2022 count), of which roughly 13% are trucks.

How long is Irr-Fm over Iowa River Overflow?

The structure is 68 ft (20.7 m) long with a longest span of 33 ft (10.1 m) and a deck 32 ft wide.

Who owns Irr-Fm over Iowa River Overflow?

It is owned by the County Highway Agency.