US Bridges

FM over Sm Stream

Fair

Washington County, Iowa · 074092904 · Structure no. 000000000336111

Built
1974
51 years old
Condition
Fair
inspected February 2023
Type
Culvert
Concrete Continuous
Length
25 ft
2 main spans
Daily traffic
180
2022 count
Owner
County
County Highway Agency

About this bridge

FM over Sm Stream is a concrete continuous culvert carrying FM over Sm Stream in Washington County, Iowa. It was built in 1974, so it is 51 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 180 vehicles a day, roughly 16% of them trucks, projected to reach 180 by 2043. The structure is 25 ft (7.6 m) long. If it were closed, the detour would be 13 mi (21 km).

Location

Open in Google Maps
CarriesFM
CrossesSm Stream
Location074092904
RouteCounty Highway 0
CountyWashington County
StateIowa
Coordinates41.1882, -91.9214
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
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Culvert5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionFebruary 2023
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
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating48.6 US tons
Inventory rating36 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckNot applicable
Main spans2
Design loadHS 20
Structure length25 ft (7.6 m)
Longest span12 ft (3.7 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic180 (2022)
Projected traffic180 by 2043
Trucks16%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed13 mi (21 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 Sm Stream built?

It was built in 1974, making it 51 years old in 2025.

What condition is FM over Sm 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 February 2023.

How much traffic does FM over Sm Stream carry?

About 180 vehicles per day (2022 count), of which roughly 16% are trucks.

How long is FM over Sm Stream?

The structure is 25 ft (7.6 m) long with a longest span of 12 ft (3.7 m).

Who owns FM over Sm Stream?

It is owned by the County Highway Agency.