US Bridges

FM over Twelve Mile Creek

FairPosted for load

Union County, Iowa · 071290204 · Structure no. 000000000324620

Built
1957
68 years old
Condition
Fair
inspected October 2023
Type
Slab
Concrete Continuous
Length
127 ft
3 main spans
Daily traffic
40
2022 count
Owner
County
County Highway Agency

About this bridge

FM over Twelve Mile Creek is a concrete continuous slab carrying FM over Twelve Mile Creek in Union County, Iowa. It was built in 1957, 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. Its operating status is: posted for load restriction.

It carries about 40 vehicles a day, projected to reach 40 by 2043. The structure is 127 ft (38.7 m) long and 23 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesFM
CrossesTwelve Mile Creek
Location071290204
RouteCounty Highway 0
CountyUnion County
StateIowa
Coordinates40.97764, -94.15279
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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
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 inspectionOctober 2023
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; scour above top of footing
Structural evaluation2: Basically intolerable, requiring high priority of replacement
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating33.1 US tons
Inventory rating11 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadH 15
Structure length127 ft (38.7 m)
Longest span49 ft (14.9 m)
Deck width23 ft (6.9 m)
Roadway width20 ft (6.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic40 (2022)
Projected traffic40 by 2043
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 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 Twelve Mile Creek built?

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

What condition is FM over Twelve Mile 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 October 2023.

How much traffic does FM over Twelve Mile Creek carry?

About 40 vehicles per day (2022 count).

How long is FM over Twelve Mile Creek?

The structure is 127 ft (38.7 m) long with a longest span of 49 ft (14.9 m) and a deck 23 ft wide.

Who owns FM over Twelve Mile Creek?

It is owned by the County Highway Agency.