US Bridges

FM over South River

FairPosted for load

Warren County, Iowa · 074250102 · Structure no. 000000000333290

Built
1950
75 years old
Condition
Fair
inspected October 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
183 ft
3 main spans
Daily traffic
11
2022 count
Owner
County
County Highway Agency

About this bridge

FM over South River is a steel continuous stringer/multi-beam or girder carrying FM over South River in Warren County, Iowa. It was built in 1950, so it is 75 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 11 vehicles a day, projected to reach 11 by 2043. The structure is 183 ft (55.8 m) long and 22 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesFM
CrossesSouth River
Location074250102
RouteCounty Highway 0
CountyWarren County
StateIowa
Coordinates41.24069, -93.69297
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.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionOctober 2023
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating32.4 US tons
Inventory rating19.4 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadH 15
Structure length183 ft (55.8 m)
Longest span70 ft (21.3 m)
Deck width22 ft (6.7 m)
Roadway width20 ft (6.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic11 (2022)
Projected traffic11 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 proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$2.2 million (2023 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was FM over South River built?

It was built in 1950, making it 75 years old in 2025.

What condition is FM over South River 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 South River carry?

About 11 vehicles per day (2022 count).

How long is FM over South River?

The structure is 183 ft (55.8 m) long with a longest span of 70 ft (21.3 m) and a deck 22 ft wide.

Who owns FM over South River?

It is owned by the County Highway Agency.