US Bridges

FM over Rock Creek

Good

Benton County, Iowa · 085120602 · Structure no. 000000000072861

Built
2006
19 years old
Condition
Good
inspected May 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
83 ft
1 main span
Daily traffic
1,340
2021 count
Owner
County
County Highway Agency

About this bridge

FM over Rock Creek is a prestressed concrete stringer/multi-beam or girder carrying FM over Rock Creek in Benton County, Iowa. It was built in 2006, so it is 19 years old, younger 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 1,340 vehicles a day, projected to reach 1,340 by 2043. The structure is 83 ft (25.3 m) long and 33 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

CarriesFM
CrossesRock Creek
Location085120602
RouteCounty Highway 0
StateIowa
Coordinates42.20451, -92.29894
Functional classRural Major 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.
Superstructure8 Very GoodNo problems noted.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionMay 2023
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating93.1 US tons
Inventory rating38.9 US tons

Structure

MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length83 ft (25.3 m)
Longest span80 ft (24.4 m)
Deck width33 ft (10.1 m)
Roadway width31 ft (9.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,340 (2021)
Projected traffic1,340 by 2043
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 2006, making it 19 years old in 2025.

What condition is FM over Rock Creek 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 May 2023.

How much traffic does FM over Rock Creek carry?

About 1,340 vehicles per day (2021 count).

How long is FM over Rock Creek?

The structure is 83 ft (25.3 m) long with a longest span of 80 ft (24.4 m) and a deck 33 ft wide.

Who owns FM over Rock Creek?

It is owned by the County Highway Agency.