US Bridges

NB US 61 over US 30 & W.11th ST

Fair

Clinton County, Iowa · At N Jct. of US 30 · Structure no. 000000000602860

Built
1970
55 years old
Condition
Fair
inspected July 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
257 ft
4 main spans
Daily traffic
6,950
2022 count
Owner
State
State Highway Agency

About this bridge

NB US 61 over US 30 & W.11th ST is a prestressed concrete stringer/multi-beam or girder carrying NB US 61 over US 30 & W.11th ST in Clinton County, Iowa. It was built in 1970, so it is 55 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 6,950 vehicles a day, roughly 16% of them trucks, projected to reach 6,950 by 2043. The structure is 257 ft (78.3 m) long and 57 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

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CarriesNB US 61
CrossesUS 30 & W.11th ST
LocationAt N Jct. of US 30
RouteU.S. Route 30
CountyClinton County
StateIowa
Coordinates41.82529, -90.56928
Functional classRural Principal Arterial - Other

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Last inspectionJuly 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 alignment8: Equal to present desirable criteria
Operating rating71.3 US tons
Inventory rating48.5 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20
Structure length257 ft (78.3 m)
Longest span77 ft (23.5 m)
Deck width57 ft (17.4 m)
Roadway width53 ft (16.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic6,950 (2022)
Projected traffic6,950 by 2043
Trucks16%
Lanes on structure3
Traffic directionOne-way traffic
CarriesOverpass structure at an interchange
CrossesHighway
Detour if closed1.2 mi (2 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—
NavigationNot applicable (no waterway)

Frequently asked questions

When was NB US 61 over US 30 & W.11th ST built?

It was built in 1970, making it 55 years old in 2025.

What condition is NB US 61 over US 30 & W.11th ST 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 July 2023.

How much traffic does NB US 61 over US 30 & W.11th ST carry?

About 6,950 vehicles per day (2022 count), of which roughly 16% are trucks.

How long is NB US 61 over US 30 & W.11th ST?

The structure is 257 ft (78.3 m) long with a longest span of 77 ft (23.5 m) and a deck 57 ft wide.

Who owns NB US 61 over US 30 & W.11th ST?

It is owned by the State Highway Agency.