US Bridges

Calonder RD over Middle Maquoketa River

Fair

Dubuque County, Iowa · 090E13106 · Structure no. 000000000147861

Built
1974
51 years old
Condition
Fair
inspected April 2023
Type
Slab
Concrete Continuous
Length
116 ft
3 main spans
Daily traffic
160
2021 count
Owner
County
County Highway Agency

About this bridge

Calonder RD over Middle Maquoketa River is a concrete continuous slab carrying Calonder RD over Middle Maquoketa River in Dubuque County, Iowa. It was built in 1974, so it is 51 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 6 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 160 vehicles a day, projected to reach 160 by 2043. The structure is 116 ft (35.4 m) long and 32 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

Location

Open in Google Maps
CarriesCalonder RD
CrossesMiddle Maquoketa River
Location090E13106
RouteCounty Highway 0
CountyDubuque County
StateIowa
Coordinates42.56402, -90.89242
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionApril 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating54 US tons
Inventory rating31.5 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadH 20
Structure length116 ft (35.4 m)
Longest span44 ft (13.4 m)
Deck width32 ft (9.8 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic160 (2021)
Projected traffic160 by 2043
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.2 mi (10 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—
NavigationNo navigation control on waterway

Frequently asked questions

When was Calonder RD over Middle Maquoketa River built?

It was built in 1974, making it 51 years old in 2025.

What condition is Calonder RD over Middle Maquoketa River 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 April 2023.

How much traffic does Calonder RD over Middle Maquoketa River carry?

About 160 vehicles per day (2021 count).

How long is Calonder RD over Middle Maquoketa River?

The structure is 116 ft (35.4 m) long with a longest span of 44 ft (13.4 m) and a deck 32 ft wide.

Who owns Calonder RD over Middle Maquoketa River?

It is owned by the County Highway Agency.