US Bridges

390th ST over Drainage Ditch

Good

Hamilton County, Iowa · 086263203 · Structure no. 000000000364815

Built
2004
21 years old
Condition
Good
inspected September 2020
Type
Culvert
Steel
Length
24 ft
1 main span
Daily traffic
20
2022 count
Owner
County
County Highway Agency

About this bridge

390th ST over Drainage Ditch is a steel culvert carrying 390th ST over Drainage Ditch in Hamilton County, Iowa. It was built in 2004, so it is 21 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 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 20 vehicles a day, projected to reach 20 by 2043. The structure is 24 ft (7.3 m) long. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
Carries390th ST
CrossesDrainage Ditch
Location086263203
RouteCounty Highway 0
CountyHamilton County
StateIowa
Coordinates42.22433, -93.89366
Functional classRural Minor Collector

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.
Culvert7 GoodSome minor problems.
Last inspectionSeptember 2020
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating57 US tons
Inventory rating51.8 US tons

Structure

Structure typeCulvert
MaterialSteel
DeckNot applicable
Main spans1
Design loadH 20
Structure length24 ft (7.3 m)
Longest span24 ft (7.3 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic20 (2022)
Projected traffic20 by 2043
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 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 proposedOther structural work, including hydraulic replacements
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was 390th ST over Drainage Ditch built?

It was built in 2004, making it 21 years old in 2025.

What condition is 390th ST over Drainage Ditch 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 September 2020.

How much traffic does 390th ST over Drainage Ditch carry?

About 20 vehicles per day (2022 count).

How long is 390th ST over Drainage Ditch?

The structure is 24 ft (7.3 m) long with a longest span of 24 ft (7.3 m).

Who owns 390th ST over Drainage Ditch?

It is owned by the County Highway Agency.