US Bridges

Central Ave over Union Hollow

Good

Dubuque County, Iowa · At Jct. Iowa #32 · Structure no. 000000000023960

Built
1967
58 years old, rebuilt 2000
Condition
Good
inspected August 2023
Type
Culvert
Concrete Continuous
Length
27 ft
2 main spans
Daily traffic
9,690
2022 count
Owner
City
City or Municipal Highway Agency

About this bridge

Central Ave over Union Hollow is a concrete continuous culvert carrying Central Ave over Union Hollow in Dubuque County, Iowa. It was built in 1967 and reconstructed in 2000, so it is 58 years old, older 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 9,690 vehicles a day, roughly 7% of them trucks, projected to reach 9,690 by 2043. The structure is 27 ft (8.2 m) long. If it were closed, the detour would be 8.7 mi (14 km).

Location

Open in Google Maps
CarriesCentral Ave
CrossesUnion Hollow
LocationAt Jct. Iowa #32
RouteCity Street 0
CountyDubuque County
StateIowa
Coordinates42.54098, -90.69314
Functional classUrban Other Principal Arterial

Condition and inspection

Good

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

ComponentRatingMeaning
Channel and channel protection7 GoodSome minor problems.
Culvert7 GoodSome minor problems.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating53.2 US tons
Inventory rating31.7 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckNot applicable
Main spans2
Design loadHS 20
Structure length27 ft (8.2 m)
Longest span16 ft (4.9 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic9,690 (2022)
Projected traffic9,690 by 2043
Trucks7%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed8.7 mi (14 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerCity or Municipal 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 Central Ave over Union Hollow built?

It was built in 1967, making it 58 years old in 2025. It was reconstructed in 2000.

What condition is Central Ave over Union Hollow 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 August 2023.

How much traffic does Central Ave over Union Hollow carry?

About 9,690 vehicles per day (2022 count), of which roughly 7% are trucks.

How long is Central Ave over Union Hollow?

The structure is 27 ft (8.2 m) long with a longest span of 16 ft (4.9 m).

Who owns Central Ave over Union Hollow?

It is owned by the City or Municipal Highway Agency and maintained by the State Highway Agency.