US Bridges

FM over Big Creek

Fair

Boone County, Iowa · 082250903 · Structure no. 000000000076891

Built
1940
85 years old, rebuilt 1983
Condition
Fair
inspected May 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
43 ft
1 main span
Daily traffic
50
2022 count
Owner
County
County Highway Agency

About this bridge

FM over Big Creek is a steel stringer/multi-beam or girder carrying FM over Big Creek in Boone County, Iowa. It was built in 1940 and reconstructed in 1983, so it is 85 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 50 vehicles a day, projected to reach 50 by 2044. The structure is 43 ft (13.1 m) long and 32 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

Location

Open in Google Maps
CarriesFM
CrossesBig Creek
Location082250903
RouteCounty Highway 0
CountyBoone County
StateIowa
Coordinates41.93609, -93.76131
Functional classRural Minor 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 inspectionMay 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating45 US tons
Inventory rating29.1 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadH 20
Structure length43 ft (13.1 m)
Longest span40 ft (12.2 m)
Deck width32 ft (9.7 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic50 (2022)
Projected traffic50 by 2044
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.2 mi (10 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 proposedOther structural work, including hydraulic replacements
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was FM over Big Creek built?

It was built in 1940, making it 85 years old in 2025. It was reconstructed in 1983.

What condition is FM over Big 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 May 2024.

How much traffic does FM over Big Creek carry?

About 50 vehicles per day (2022 count).

How long is FM over Big Creek?

The structure is 43 ft (13.1 m) long with a longest span of 40 ft (12.2 m) and a deck 32 ft wide.

Who owns FM over Big Creek?

It is owned by the County Highway Agency.