US Bridges

Ansborough Ave over US 20

Good

Black Hawk County, Iowa · 1.5 Mi. W of Jct. Ia 21 · Structure no. 000000000605210

Built
1984
41 years old
Condition
Good
inspected February 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
267 ft
4 main spans
Daily traffic
4,855
2022 count
Owner
State
State Highway Agency

About this bridge

Ansborough Ave over US 20 is a prestressed concrete stringer/multi-beam or girder carrying Ansborough Ave over US 20 in Black Hawk County, Iowa. It was built in 1984, so it is 41 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 4,855 vehicles a day, roughly 3% of them trucks, projected to reach 4,855 by 2043. The structure is 267 ft (81.4 m) long and 47 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

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CarriesAnsborough Ave
CrossesUS 20
Location1.5 Mi. W of Jct. Ia 21
RouteCity Street 0
CountyBlack Hawk County
StateIowa
Coordinates42.45327, -92.37623
Functional classUrban Minor Arterial

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.
Last inspectionFebruary 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation7: Better than present minimum criteria
Deck geometry7: Better than present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating99.8 US tons
Inventory rating48.2 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20
Structure length267 ft (81.4 m)
Longest span92 ft (28 m)
Deck width47 ft (14.4 m)
Roadway width44 ft (13.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic4,855 (2022)
Projected traffic4,855 by 2043
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
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—
NavigationNot applicable (no waterway)

Frequently asked questions

When was Ansborough Ave over US 20 built?

It was built in 1984, making it 41 years old in 2025.

What condition is Ansborough Ave over US 20 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 February 2023.

How much traffic does Ansborough Ave over US 20 carry?

About 4,855 vehicles per day (2022 count), of which roughly 3% are trucks.

How long is Ansborough Ave over US 20?

The structure is 267 ft (81.4 m) long with a longest span of 92 ft (28 m) and a deck 47 ft wide.

Who owns Ansborough Ave over US 20?

It is owned by the State Highway Agency.