US Bridges

Knox Ave over Small Creek

Fair

Woodbury County, Iowa · 089432002 · Structure no. 000000000354826

Built
1979
46 years old
Condition
Fair
inspected June 2023
Type
Culvert
Concrete Continuous
Length
36 ft
2 main spans
Daily traffic
60
2022 count
Owner
County
County Highway Agency

About this bridge

Knox Ave over Small Creek is a concrete continuous culvert carrying Knox Ave over Small Creek in Woodbury County, Iowa. It was built in 1979, so it is 46 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 60 vehicles a day, projected to reach 60 by 2043. The structure is 36 ft (11.1 m) long. If it were closed, the detour would be 1.9 mi (3 km).

Location

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CarriesKnox Ave
CrossesSmall Creek
Location089432002
RouteCounty Highway 0
CountyWoodbury County
StateIowa
Coordinates42.50937, -95.95723
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 protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Culvert5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionJune 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 adequacy5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating48.6 US tons
Inventory rating36 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckNot applicable
Main spans2
Design loadHS 20
Structure length36 ft (11.1 m)
Longest span14 ft (4.3 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic60 (2022)
Projected traffic60 by 2043
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 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$30,000 (2023 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Knox Ave over Small Creek built?

It was built in 1979, making it 46 years old in 2025.

What condition is Knox Ave over Small Creek 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 June 2023.

How much traffic does Knox Ave over Small Creek carry?

About 60 vehicles per day (2022 count).

How long is Knox Ave over Small Creek?

The structure is 36 ft (11.1 m) long with a longest span of 14 ft (4.3 m).

Who owns Knox Ave over Small Creek?

It is owned by the County Highway Agency.