US Bridges

278th ST over Rock Creek

Good

Clinton County, Iowa · 081E13506 · Structure no. 000000000121932

Built
2015
10 years old
Condition
Good
inspected December 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
80 ft
1 main span
Daily traffic
26
2022 count
Owner
County
County Highway Agency

About this bridge

278th ST over Rock Creek is a steel stringer/multi-beam or girder carrying 278th ST over Rock Creek in Clinton County, Iowa. It was built in 2015, so it is 10 years old, younger than the Iowa average of 45.5 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 9 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 26 vehicles a day, projected to reach 26 by 2043. The structure is 80 ft (24.4 m) long and 31 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

Location

Open in Google Maps
Carries278th ST
CrossesRock Creek
Location081E13506
RouteCounty Highway 0
CountyClinton County
StateIowa
Coordinates41.77903, -90.8117
Functional classRural Local

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck9 ExcellentNo problems noted.
Superstructure9 ExcellentNo problems noted.
Substructure9 ExcellentNo problems noted.
Channel and channel protection9 ExcellentNo problems noted.
Last inspectionDecember 2023
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation9: Superior to present desirable criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment5: Somewhat better than minimum adequacy to tolerate being left in place as is
Operating rating65 US tons
Inventory rating50 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1 (+2 approach)
Design loadHL 93
Structure length80 ft (24.4 m)
Longest span38 ft (11.6 m)
Deck width31 ft (9.4 m)
Roadway width30 ft (9.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic26 (2022)
Projected traffic26 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$122,000
NavigationNot applicable (no waterway)

Frequently asked questions

When was 278th ST over Rock Creek built?

It was built in 2015, making it 10 years old in 2025.

What condition is 278th ST over Rock Creek in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in December 2023.

How much traffic does 278th ST over Rock Creek carry?

About 26 vehicles per day (2022 count).

How long is 278th ST over Rock Creek?

The structure is 80 ft (24.4 m) long with a longest span of 38 ft (11.6 m) and a deck 31 ft wide.

Who owns 278th ST over Rock Creek?

It is owned by the County Highway Agency.