US Bridges

FM over Rock Creek

Fair

Tama County, Iowa · 085130102 · Structure no. 000000000319450

Built
1968
57 years old
Condition
Fair
inspected September 2024
Type
Channel Beam
Concrete
Length
37 ft
1 main span
Daily traffic
39
2022 count
Owner
County
County Highway Agency

About this bridge

FM over Rock Creek is a concrete channel beam carrying FM over Rock Creek in Tama County, Iowa. It was built in 1968, so it is 57 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 39 vehicles a day, projected to reach 39 by 2044. The structure is 37 ft (11.3 m) long and 25 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesFM
CrossesRock Creek
Location085130102
RouteCounty Highway 0
CountyTama County
StateIowa
Coordinates42.19669, -92.3188
Functional classRural Local

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.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionSeptember 2024
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 adequacy7: Better than present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating46.6 US tons
Inventory rating27.9 US tons

Structure

Structure typeChannel Beam
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadH 15
Structure length37 ft (11.3 m)
Longest span35 ft (10.7 m)
Deck width25 ft (7.7 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic39 (2022)
Projected traffic39 by 2044
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 proposedOther structural work, including hydraulic replacements
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was FM over Rock Creek built?

It was built in 1968, making it 57 years old in 2025.

What condition is FM over Rock 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 September 2024.

How much traffic does FM over Rock Creek carry?

About 39 vehicles per day (2022 count).

How long is FM over Rock Creek?

The structure is 37 ft (11.3 m) long with a longest span of 35 ft (10.7 m) and a deck 25 ft wide.

Who owns FM over Rock Creek?

It is owned by the County Highway Agency.