US Bridges

B 58 (470th St) over Six Mile Creek

Good

Sioux County, Iowa · 094481301 · Structure no. 000000000309611

Built
2012
13 years old
Condition
Good
inspected December 2022
Type
Slab
Concrete Continuous
Length
153 ft
3 main spans
Daily traffic
40
2022 count
Owner
County
County Highway Agency

About this bridge

B 58 (470th St) over Six Mile Creek is a concrete continuous slab carrying B 58 (470th St) over Six Mile Creek in Sioux County, Iowa. It was built in 2012, so it is 13 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 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 40 vehicles a day, projected to reach 40 by 2043. The structure is 153 ft (46.6 m) long and 32 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesB 58 (470th St)
CrossesSix Mile Creek
Location094481301
RouteCounty Highway 0
CountySioux County
StateIowa
Coordinates42.96764, -96.45255
Functional classRural Minor Collector

Condition and inspection

Good

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

ComponentRatingMeaning
Deck8 Very GoodNo problems noted.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionDecember 2022
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating83.2 US tons
Inventory rating49.9 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHL 93
Structure length153 ft (46.6 m)
Longest span59 ft (18 m)
Deck width32 ft (9.8 m)
Roadway width31 ft (9.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic40 (2022)
Projected traffic40 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 proposedNone recorded
Estimated improvement cost—
NavigationNot applicable (no waterway)

Frequently asked questions

When was B 58 (470th St) over Six Mile Creek built?

It was built in 2012, making it 13 years old in 2025.

What condition is B 58 (470th St) over Six Mile 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 2022.

How much traffic does B 58 (470th St) over Six Mile Creek carry?

About 40 vehicles per day (2022 count).

How long is B 58 (470th St) over Six Mile Creek?

The structure is 153 ft (46.6 m) long with a longest span of 59 ft (18 m) and a deck 32 ft wide.

Who owns B 58 (470th St) over Six Mile Creek?

It is owned by the County Highway Agency.