US Bridges

18th ST over Duck Creek

PoorPosted for load

Scott County, Iowa · Bettendorf Ia · Structure no. 000000000000670

Built
1962
63 years old, rebuilt 1990
Condition
Poor
inspected July 2023
Type
Slab
Concrete Continuous
Length
125 ft
3 main spans
Daily traffic
4,210
2022 count
Owner
City
City or Municipal Highway Agency

About this bridge

18th ST over Duck Creek is a concrete continuous slab carrying 18th ST over Duck Creek in Scott County, Iowa. It was built in 1962 and reconstructed in 1990, so it is 63 years old, older than the Iowa average of 45.5 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. Its operating status is: posted for load restriction.

It carries about 4,210 vehicles a day, projected to reach 4,210 by 2043. The structure is 125 ft (38.1 m) long and 52 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
Carries18th ST
CrossesDuck Creek
LocationBettendorf Ia
RouteCity Street 0
CountyScott County
StateIowa
Coordinates41.53912, -90.50708
Functional classUrban Minor Arterial

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Deck4 PoorAdvanced section loss, deterioration, spalling or scour.
Superstructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionJuly 2023
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; scour above top of footing
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating39.1 US tons
Inventory rating23.4 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadH 20
Structure length125 ft (38.1 m)
Longest span49 ft (14.9 m)
Deck width52 ft (15.7 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic4,210 (2022)
Projected traffic4,210 by 2043
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCity or Municipal Highway Agency
Maintained byCity or Municipal 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 18th ST over Duck Creek built?

It was built in 1962, making it 63 years old in 2025. It was reconstructed in 1990.

What condition is 18th ST over Duck Creek in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in July 2023.

How much traffic does 18th ST over Duck Creek carry?

About 4,210 vehicles per day (2022 count).

How long is 18th ST over Duck Creek?

The structure is 125 ft (38.1 m) long with a longest span of 49 ft (14.9 m) and a deck 52 ft wide.

Who owns 18th ST over Duck Creek?

It is owned by the City or Municipal Highway Agency.