US Bridges

FM over Tarkio Creek

Fair

Montgomery County, Iowa · 072372801 · Structure no. 000000000255391

Built
1978
47 years old
Condition
Fair
inspected June 2024
Type
Slab
Concrete Continuous
Length
128 ft
3 main spans
Daily traffic
509
2022 count
Owner
County
County Highway Agency

About this bridge

FM over Tarkio Creek is a concrete continuous slab carrying FM over Tarkio Creek in Montgomery County, Iowa. It was built in 1978, so it is 47 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 5 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 509 vehicles a day, roughly 11% of them trucks, projected to reach 509 by 2044. The structure is 128 ft (39 m) long and 32 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesFM
CrossesTarkio Creek
Location072372801
RouteCounty Highway 0
CountyMontgomery County
StateIowa
Coordinates41.01597, -95.114
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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure7 GoodSome minor problems.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJune 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating57.4 US tons
Inventory rating33.3 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadH 20
Structure length128 ft (39 m)
Longest span49 ft (14.9 m)
Deck width32 ft (9.8 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic509 (2022)
Projected traffic509 by 2044
Trucks11%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 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 proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was FM over Tarkio Creek built?

It was built in 1978, making it 47 years old in 2025.

What condition is FM over Tarkio Creek 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 June 2024.

How much traffic does FM over Tarkio Creek carry?

About 509 vehicles per day (2022 count), of which roughly 11% are trucks.

How long is FM over Tarkio Creek?

The structure is 128 ft (39 m) long with a longest span of 49 ft (14.9 m) and a deck 32 ft wide.

Who owns FM over Tarkio Creek?

It is owned by the County Highway Agency.