US Bridges

FM over Little Tarkio

PoorPosted for load

Montgomery County, Iowa · 071383501 · Structure no. 000000000254800

Built
1958
67 years old
Condition
Poor
inspected May 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
103 ft
3 main spans
Daily traffic
219
2021 count
Owner
County
County Highway Agency

About this bridge

FM over Little Tarkio is a prestressed concrete stringer/multi-beam or girder carrying FM over Little Tarkio in Montgomery County, Iowa. It was built in 1958, so it is 67 years old, older than the Iowa average of 45.5 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. Its operating status is: posted for other load-capacity restriction.

It carries about 219 vehicles a day, projected to reach 219 by 2043. The structure is 103 ft (31.4 m) long and 23 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesFM
CrossesLittle Tarkio
Location071383501
RouteCounty Highway 0
CountyMontgomery County
StateIowa
Coordinates40.91559, -95.18895
Functional classRural Major Collector

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Deck4 PoorAdvanced section loss, deterioration, spalling or scour.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusPosted for other load-capacity restriction
ScourFoundations stable; scour above top of footing
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating41.6 US tons
Inventory rating26.8 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans3
Design loadH 15
Structure length103 ft (31.4 m)
Longest span43 ft (13.1 m)
Deck width23 ft (6.9 m)
Roadway width20 ft (6.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic219 (2021)
Projected traffic219 by 2043
Trucks0%
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 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 Little Tarkio built?

It was built in 1958, making it 67 years old in 2025.

What condition is FM over Little Tarkio in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in May 2023.

How much traffic does FM over Little Tarkio carry?

About 219 vehicles per day (2021 count).

How long is FM over Little Tarkio?

The structure is 103 ft (31.4 m) long with a longest span of 43 ft (13.1 m) and a deck 23 ft wide.

Who owns FM over Little Tarkio?

It is owned by the County Highway Agency.