US Bridges

US 20 over N Branch Catfish Creek

Fair

Dubuque County, Iowa · 1.7 Mi. E of Jct. Ia 32 · Structure no. 000000000023860

Built
1939
86 years old, rebuilt 1961
Condition
Fair
inspected January 2024
Type
Culvert
Concrete
Length
38 ft
1 main span
Daily traffic
33,600
2022 count
Owner
State
State Highway Agency

About this bridge

US 20 over N Branch Catfish Creek is a concrete culvert carrying US 20 over N Branch Catfish Creek in Dubuque County, Iowa. It was built in 1939 and reconstructed in 1961, so it is 86 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 5 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 33,600 vehicles a day, roughly 7% of them trucks, projected to reach 33,600 by 2044. The structure is 38 ft (11.6 m) long. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesUS 20
CrossesN Branch Catfish Creek
Location1.7 Mi. E of Jct. Ia 32
RouteU.S. Route 20
CountyDubuque County
StateIowa
Coordinates42.4918, -90.70614
Functional classUrban Other Principal Arterial

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Channel and channel protection7 GoodSome minor problems.
Culvert5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionJanuary 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating110.1 US tons
Inventory rating110.1 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans1
Design loadH 15
Structure length38 ft (11.6 m)
Longest span38 ft (11.6 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic33,600 (2022)
Projected traffic33,600 by 2044
Trucks7%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 km)
TollOn a free road
National Highway SystemYes

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—
NavigationNo navigation control on waterway

Frequently asked questions

When was US 20 over N Branch Catfish Creek built?

It was built in 1939, making it 86 years old in 2025. It was reconstructed in 1961.

What condition is US 20 over N Branch Catfish Creek 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 January 2024.

How much traffic does US 20 over N Branch Catfish Creek carry?

About 33,600 vehicles per day (2022 count), of which roughly 7% are trucks.

How long is US 20 over N Branch Catfish Creek?

The structure is 38 ft (11.6 m) long with a longest span of 38 ft (11.6 m).

Who owns US 20 over N Branch Catfish Creek?

It is owned by the State Highway Agency.