US Bridges

FM over Small Stream

Fair

Lyon County, Iowa · 098460902 · Structure no. 000000000228750

Built
1946
79 years old
Condition
Fair
inspected July 2023
Type
Culvert
Concrete Continuous
Length
21 ft
2 main spans
Daily traffic
509
2022 count
Owner
County
County Highway Agency

About this bridge

FM over Small Stream is a concrete continuous culvert carrying FM over Small Stream in Lyon County, Iowa. It was built in 1946, so it is 79 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 6 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 509 vehicles a day, roughly 22% of them trucks, projected to reach 509 by 2043. The structure is 21 ft (6.4 m) long and 30 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesFM
CrossesSmall Stream
Location098460902
RouteCounty Highway 0
CountyLyon County
StateIowa
Coordinates43.32486, -96.29455
Functional classRural Major 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
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Culvert6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJuly 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating70.5 US tons
Inventory rating42.3 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckNot applicable
Main spans2
Design loadH 15
Structure length21 ft (6.4 m)
Longest span10 ft (3 m)
Deck width30 ft (9.1 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic509 (2022)
Projected traffic509 by 2043
Trucks22%
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 Small Stream built?

It was built in 1946, making it 79 years old in 2025.

What condition is FM over Small Stream 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 July 2023.

How much traffic does FM over Small Stream carry?

About 509 vehicles per day (2022 count), of which roughly 22% are trucks.

How long is FM over Small Stream?

The structure is 21 ft (6.4 m) long with a longest span of 10 ft (3 m) and a deck 30 ft wide.

Who owns FM over Small Stream?

It is owned by the County Highway Agency.