US Bridges

FM over S Coal Creek

FairPosted for load

Mahaska County, Iowa · 074171004 · Structure no. 000000000235930

Built
1951
74 years old
Condition
Fair
inspected December 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
54 ft
1 main span
Daily traffic
10
2022 count
Owner
County
County Highway Agency

About this bridge

FM over S Coal Creek is a steel stringer/multi-beam or girder carrying FM over S Coal Creek in Mahaska County, Iowa. It was built in 1951, so it is 74 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. Its operating status is: posted for load restriction.

It carries about 10 vehicles a day, projected to reach 10 by 2043. The structure is 54 ft (16.5 m) long and 22 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesFM
CrossesS Coal Creek
Location074171004
RouteCounty Highway 0
CountyMahaska County
StateIowa
Coordinates41.22228, -92.80897
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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionDecember 2023
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment5: Somewhat better than minimum adequacy to tolerate being left in place as is
Operating rating45.2 US tons
Inventory rating27.1 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadH 15
Structure length54 ft (16.5 m)
Longest span51 ft (15.5 m)
Deck width22 ft (6.7 m)
Roadway width20 ft (6.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic10 (2022)
Projected traffic10 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$594,000 (2024 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was FM over S Coal Creek built?

It was built in 1951, making it 74 years old in 2025.

What condition is FM over S Coal 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 December 2023.

How much traffic does FM over S Coal Creek carry?

About 10 vehicles per day (2022 count).

How long is FM over S Coal Creek?

The structure is 54 ft (16.5 m) long with a longest span of 51 ft (15.5 m) and a deck 22 ft wide.

Who owns FM over S Coal Creek?

It is owned by the County Highway Agency.