US Bridges

Ia 39 over Natural Stream

Fair

Sac County, Iowa · 2.6 Mi. S of SR D59 · Structure no. 000000000700865

Built
1951
74 years old
Condition
Fair
inspected April 2024
Type
Culvert
Concrete Continuous
Length
22 ft
2 main spans
Daily traffic
1,540
2022 count
Owner
State
State Highway Agency

About this bridge

Ia 39 over Natural Stream is a concrete continuous culvert carrying Ia 39 over Natural Stream in Sac County, Iowa. It was built in 1951, so it is 74 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 1,540 vehicles a day, roughly 40% of them trucks, projected to reach 1,540 by 2044. The structure is 22 ft (6.7 m) long. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesIa 39
CrossesNatural Stream
Location2.6 Mi. S of SR D59
RouteState Highway 39
CountySac County
StateIowa
Coordinates42.23124, -95.24591
Functional classRural Minor Arterial

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.
Culvert6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionApril 2024
Inspection intervalevery 23 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 adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating27 US tons
Inventory rating20 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckNot applicable
Main spans2
Design loadH 20
Structure length22 ft (6.7 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 traffic1,540 (2022)
Projected traffic1,540 by 2044
Trucks40%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Ia 39 over Natural Stream built?

It was built in 1951, making it 74 years old in 2025.

What condition is Ia 39 over Natural 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 April 2024.

How much traffic does Ia 39 over Natural Stream carry?

About 1,540 vehicles per day (2022 count), of which roughly 40% are trucks.

How long is Ia 39 over Natural Stream?

The structure is 22 ft (6.7 m) long with a longest span of 10 ft (3 m).

Who owns Ia 39 over Natural Stream?

It is owned by the State Highway Agency.