US Bridges

FM over Frog Creek

Fair

Dallas County, Iowa · 081280903 · Structure no. 000000000132570

Built
1920
105 years old
Condition
Fair
inspected November 2022
Type
Stringer/Multi-beam or Girder
Steel
Length
30 ft
1 main span
Daily traffic
428
2022 count
Owner
County
County Highway Agency

About this bridge

FM over Frog Creek is a steel stringer/multi-beam or girder carrying FM over Frog Creek in Dallas County, Iowa. It was built in 1920, so it is 105 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 428 vehicles a day, roughly 20% of them trucks, projected to reach 428 by 2043. The structure is 30 ft (9.1 m) long and 28 ft wide. If it were closed, the detour would be 5 mi (8 km).

Location

Open in Google Maps
CarriesFM
CrossesFrog Creek
Location081280903
RouteCounty Highway 0
CountyDallas County
StateIowa
Coordinates41.84931, -94.11457
Functional classUrban 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.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionNovember 2022
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 geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment7: Better than present minimum criteria
Operating rating50.8 US tons
Inventory rating32.1 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadUnknown
Structure length30 ft (9.1 m)
Longest span28 ft (8.5 m)
Deck width28 ft (8.5 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic428 (2022)
Projected traffic428 by 2043
Trucks20%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed5 mi (8 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 Frog Creek built?

It was built in 1920, making it 105 years old in 2025.

What condition is FM over Frog 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 November 2022.

How much traffic does FM over Frog Creek carry?

About 428 vehicles per day (2022 count), of which roughly 20% are trucks.

How long is FM over Frog Creek?

The structure is 30 ft (9.1 m) long with a longest span of 28 ft (8.5 m) and a deck 28 ft wide.

Who owns FM over Frog Creek?

It is owned by the County Highway Agency.