US Bridges

US 218 over Trib-Shell Rock River

Fair

Bremer County, Iowa · 1.1 Mi. N of Jct. Ia 3 · Structure no. 000000000601740

Built
1996
29 years old
Condition
Fair
inspected March 2023
Type
Culvert
Concrete Continuous
Length
28 ft
2 main spans
Daily traffic
8,300
2022 count
Owner
State
State Highway Agency

About this bridge

US 218 over Trib-Shell Rock River is a concrete continuous culvert carrying US 218 over Trib-Shell Rock River in Bremer County, Iowa. It was built in 1996, so it is 29 years old, younger 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 8,300 vehicles a day, roughly 24% of them trucks, projected to reach 8,300 by 2042. The structure is 28 ft (8.5 m) long. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesUS 218
CrossesTrib-Shell Rock River
Location1.1 Mi. N of Jct. Ia 3
RouteU.S. Route 218
CountyBremer County
StateIowa
Coordinates42.73093, -92.53343
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 protection8 Very GoodNo problems noted.
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 evaluation6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating55.9 US tons
Inventory rating33.5 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckNot applicable
Main spans2
Design loadHS 20
Structure length28 ft (8.5 m)
Longest span13 ft (4 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic8,300 (2022)
Projected traffic8,300 by 2042
Trucks24%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
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 US 218 over Trib-Shell Rock River built?

It was built in 1996, making it 29 years old in 2025.

What condition is US 218 over Trib-Shell Rock River 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 218 over Trib-Shell Rock River carry?

About 8,300 vehicles per day (2022 count), of which roughly 24% are trucks.

How long is US 218 over Trib-Shell Rock River?

The structure is 28 ft (8.5 m) long with a longest span of 13 ft (4 m).

Who owns US 218 over Trib-Shell Rock River?

It is owned by the State Highway Agency.