US Bridges

FM over Nishnabotna Trib

Fair

Montgomery County, Iowa · 073381304 · Structure no. 000000000256550

Built
1957
68 years old, rebuilt 2003
Condition
Fair
inspected May 2023
Type
Stringer/Multi-beam or Girder
Concrete
Length
24 ft
1 main span
Daily traffic
34
2021 count
Owner
County
County Highway Agency

About this bridge

FM over Nishnabotna Trib is a concrete stringer/multi-beam or girder carrying FM over Nishnabotna Trib in Montgomery County, Iowa. It was built in 1957 and reconstructed in 2003, so it is 68 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 34 vehicles a day, projected to reach 34 by 2043. The structure is 24 ft (7.3 m) long and 26 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesFM
CrossesNishnabotna Trib
Location073381304
RouteCounty Highway 0
CountyMontgomery County
StateIowa
Coordinates41.11776, -95.17518
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
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMay 2023
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 adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating65 US tons
Inventory rating38.9 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialConcrete
DeckConcrete, precast panels
Main spans1
Design loadHS 20
Structure length24 ft (7.3 m)
Longest span23 ft (7 m)
Deck width26 ft (7.8 m)
Roadway width25 ft (7.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic34 (2021)
Projected traffic34 by 2043
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 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 Nishnabotna Trib built?

It was built in 1957, making it 68 years old in 2025. It was reconstructed in 2003.

What condition is FM over Nishnabotna Trib 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 May 2023.

How much traffic does FM over Nishnabotna Trib carry?

About 34 vehicles per day (2021 count).

How long is FM over Nishnabotna Trib?

The structure is 24 ft (7.3 m) long with a longest span of 23 ft (7 m) and a deck 26 ft wide.

Who owns FM over Nishnabotna Trib?

It is owned by the County Highway Agency.