US Bridges

78th ST over Silver Creek

Good

Howard County, Iowa · 099111103 · Structure no. 000000000182831

Built
2013
12 years old
Condition
Good
inspected March 2021
Type
Culvert
Concrete Continuous
Length
56 ft
4 main spans
Daily traffic
30
2022 count
Owner
County
County Highway Agency

About this bridge

78th ST over Silver Creek is a concrete continuous culvert carrying 78th ST over Silver Creek in Howard County, Iowa. It was built in 2013, so it is 12 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 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 30 vehicles a day, projected to reach 30 by 2043. The structure is 56 ft (17.1 m) long. If it were closed, the detour would be 5 mi (8 km).

Location

Open in Google Maps
Carries78th ST
CrossesSilver Creek
Location099111103
RouteCounty Highway 0
CountyHoward County
StateIowa
Coordinates43.40379, -92.11249
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
Channel and channel protection8 Very GoodNo problems noted.
Culvert8 Very GoodNo problems noted.
Last inspectionMarch 2021
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating48.2 US tons
Inventory rating35.7 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckNot applicable
Main spans4
Design loadHL 93
Structure length56 ft (17.1 m)
Longest span14 ft (4.2 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic30 (2022)
Projected traffic30 by 2043
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed5 mi (8 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—
NavigationNo navigation control on waterway

Frequently asked questions

When was 78th ST over Silver Creek built?

It was built in 2013, making it 12 years old in 2025.

What condition is 78th ST over Silver 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 March 2021.

How much traffic does 78th ST over Silver Creek carry?

About 30 vehicles per day (2022 count).

How long is 78th ST over Silver Creek?

The structure is 56 ft (17.1 m) long with a longest span of 14 ft (4.2 m).

Who owns 78th ST over Silver Creek?

It is owned by the County Highway Agency.