US Bridges

US 6 over Ralston Creek

Fair

Johnson County, Iowa · 0.3 Mi. E of E Jct. Ia #1 · Structure no. 000000000031580

Built
1957
68 years old
Condition
Fair
inspected March 2023
Type
Culvert
Concrete Continuous
Length
33 ft
2 main spans
Daily traffic
27,600
2022 count
Owner
State
State Highway Agency

About this bridge

US 6 over Ralston Creek is a concrete continuous culvert carrying US 6 over Ralston Creek in Johnson County, Iowa. It was built in 1957, so it is 68 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 27,600 vehicles a day, roughly 3% of them trucks, projected to reach 27,600 by 2042. The structure is 33 ft (10.1 m) long. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesUS 6
CrossesRalston Creek
Location0.3 Mi. E of E Jct. Ia #1
RouteU.S. Route 6
CountyJohnson County
StateIowa
Coordinates41.6461, -91.53486
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.
Culvert6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMarch 2023
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 adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating38.4 US tons
Inventory rating23 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckNot applicable
Main spans2
Design loadH 20
Structure length33 ft (10.1 m)
Longest span14 ft (4.3 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic27,600 (2022)
Projected traffic27,600 by 2042
Trucks3%
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 6 over Ralston Creek built?

It was built in 1957, making it 68 years old in 2025.

What condition is US 6 over Ralston 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 March 2023.

How much traffic does US 6 over Ralston Creek carry?

About 27,600 vehicles per day (2022 count), of which roughly 3% are trucks.

How long is US 6 over Ralston Creek?

The structure is 33 ft (10.1 m) long with a longest span of 14 ft (4.3 m).

Who owns US 6 over Ralston Creek?

It is owned by the State Highway Agency.