US Bridges

230th ST over Walnut Creek

Good

Poweshiek County, Iowa · 81130202 · Structure no. 000000000293961

Built
2009
16 years old
Condition
Good
inspected December 2023
Type
Slab
Steel
Length
100 ft
2 main spans
Daily traffic
20
2022 count
Owner
County
County Highway Agency

About this bridge

230th ST over Walnut Creek is a steel slab carrying 230th ST over Walnut Creek in Poweshiek County, Iowa. It was built in 2009, so it is 16 years old, younger than the Iowa average of 45.5 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 20 vehicles a day, projected to reach 20 by 2043. The structure is 100 ft (30.5 m) long and 30 ft wide. If it were closed, the detour would be 123.7 mi (199 km).

Location

Open in Google Maps
Carries230th ST
CrossesWalnut Creek
Location81130202
RouteCounty Highway 0
CountyPoweshiek County
StateIowa
Coordinates41.85199, -92.33751
Functional classRural Local

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionDecember 2023
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy4: Meets minimum tolerable limits to be left in place as is
Approach roadway alignment5: Somewhat better than minimum adequacy to tolerate being left in place as is
Operating rating89.7 US tons
Inventory rating53.8 US tons

Structure

Structure typeSlab
MaterialSteel
DeckConcrete, cast-in-place
Main spans2
Design loadHS 20
Structure length100 ft (30.5 m)
Longest span50 ft (15.2 m)
Deck width30 ft (9.2 m)
Roadway width30 ft (9.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic20 (2022)
Projected traffic20 by 2043
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed123.7 mi (199 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 (2024 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was 230th ST over Walnut Creek built?

It was built in 2009, making it 16 years old in 2025.

What condition is 230th ST over Walnut Creek in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in December 2023.

How much traffic does 230th ST over Walnut Creek carry?

About 20 vehicles per day (2022 count).

How long is 230th ST over Walnut Creek?

The structure is 100 ft (30.5 m) long with a longest span of 50 ft (15.2 m) and a deck 30 ft wide.

Who owns 230th ST over Walnut Creek?

It is owned by the County Highway Agency.