US Bridges

FM over I-29

Good

Monona County, Iowa · 2.3 Mi. N of SR E24 · Structure no. 000000000037340

Built
1959
66 years old
Condition
Good
inspected June 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
218 ft
4 main spans
Daily traffic
50
2021 count
Owner
State
State Highway Agency

About this bridge

FM over I-29 is a prestressed concrete stringer/multi-beam or girder carrying FM over I-29 in Monona County, Iowa. It was built in 1959, so it is 66 years old, older than the Iowa average of 45.5 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 50 vehicles a day, roughly 16% of them trucks, projected to reach 50 by 2043. The structure is 218 ft (66.4 m) long and 29 ft wide.

CarriesFM
CrossesI-29
Location2.3 Mi. N of SR E24
RouteCounty Highway 0
StateIowa
Coordinates42.15821, -96.22421
Functional classRural Minor Collector

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Last inspectionJune 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry6: Equal to present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating50.2 US tons
Inventory rating13.6 US tons

Structure

MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans4
Design loadH 15
Structure length218 ft (66.4 m)
Longest span65 ft (19.8 m)
Deck width29 ft (8.7 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic50 (2021)
Projected traffic50 by 2043
Trucks16%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed—
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNot applicable (no waterway)

Frequently asked questions

When was FM over I-29 built?

It was built in 1959, making it 66 years old in 2025.

What condition is FM over I-29 in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in June 2023.

How much traffic does FM over I-29 carry?

About 50 vehicles per day (2021 count), of which roughly 16% are trucks.

How long is FM over I-29?

The structure is 218 ft (66.4 m) long with a longest span of 65 ft (19.8 m) and a deck 29 ft wide.

Who owns FM over I-29?

It is owned by the State Highway Agency.