US Bridges

FM over Small Natural Stream

Poor

Decatur County, Iowa · 070273418 · Structure no. 000000000022800

Built
1939
86 years old
Condition
Poor
inspected November 2023
Type
Culvert
Concrete Continuous
Length
21 ft
2 main spans
Daily traffic
278
2022 count
Owner
County
County Highway Agency

About this bridge

FM over Small Natural Stream is a concrete continuous culvert carrying FM over Small Natural Stream in Decatur County, Iowa. It was built in 1939, so it is 86 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 4 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.

It carries about 278 vehicles a day, roughly 24% of them trucks, projected to reach 278 by 2043. The structure is 21 ft (6.4 m) long. If it were closed, the detour would be 26.7 mi (43 km).

Location

Open in Google Maps
CarriesFM
CrossesSmall Natural Stream
Location070273418
RouteCounty Highway 0
CountyDecatur County
StateIowa
Coordinates40.8139, -93.95723
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 protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Culvert4 PoorAdvanced section loss, deterioration, spalling or scour.
Last inspectionNovember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating110.1 US tons
Inventory rating80.8 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 width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic278 (2022)
Projected traffic278 by 2043
Trucks24%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed26.7 mi (43 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 Natural Stream built?

It was built in 1939, making it 86 years old in 2025.

What condition is FM over Small Natural 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 November 2023.

How much traffic does FM over Small Natural Stream carry?

About 278 vehicles per day (2022 count), of which roughly 24% are trucks.

How long is FM over Small Natural Stream?

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

Who owns FM over Small Natural Stream?

It is owned by the County Highway Agency.