US Bridges

FM over Sm Stream

PoorPosted for load

Louisa County, Iowa · 073041104 · Structure no. 000000000223815

Built
1950
75 years old
Condition
Poor
inspected May 2024
Type
Culvert
Concrete Continuous
Length
24 ft
2 main spans
Daily traffic
490
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 Louisa 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 poor condition with a lowest component rating of 3 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. Its operating status is: posted for load restriction.

It carries about 490 vehicles a day, roughly 10% of them trucks, projected to reach 490 by 2044. The structure is 24 ft (7.3 m) long. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesFM
CrossesSm Stream
Location073041104
RouteCounty Highway 0
CountyLouisa County
StateIowa
Coordinates41.13718, -91.27977
Functional classRural Major Collector

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Channel and channel protection4 PoorAdvanced section loss, deterioration, spalling or scour.
Culvert3 SeriousLoss of section, deterioration, spalling or scour have seriously affected primary structural components.
Last inspectionMay 2024
Inspection intervalevery 12 months
Operating statusPosted for load restriction
ScourFoundations stable; scour above top of footing
Structural evaluation3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment6: Equal to present minimum criteria
Operating rating36 US tons
Inventory rating25 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckNot applicable
Main spans2
Design loadUnknown
Structure length24 ft (7.3 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 traffic490 (2022)
Projected traffic490 by 2044
Trucks10%
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 statusPossibly eligible for the National Register; requires further investigation
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 Sm Stream built?

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

What condition is FM over Sm Stream in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in May 2024.

How much traffic does FM over Sm Stream carry?

About 490 vehicles per day (2022 count), of which roughly 10% are trucks.

How long is FM over Sm Stream?

The structure is 24 ft (7.3 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.