US Bridges

70th ST over Drainage Ditch

Good

Howard County, Iowa · 099121103 · Structure no. 000000000182971

Built
2018
7 years old
Condition
Good
inspected April 2022
Type
Slab
Steel
Length
25 ft
1 main span
Daily traffic
35
2022 count
Owner
County
County Highway Agency

About this bridge

70th ST over Drainage Ditch is a steel slab carrying 70th ST over Drainage Ditch in Howard County, Iowa. It was built in 2018, so it is 7 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 35 vehicles a day, projected to reach 35 by 2043. The structure is 25 ft (7.7 m) long and 24 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
Carries70th ST
CrossesDrainage Ditch
Location099121103
RouteCounty Highway 0
CountyHoward County
StateIowa
Coordinates43.4144, -92.22271
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
Deck8 Very GoodNo problems noted.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionApril 2022
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Deck geometry5: 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 rating110.1 US tons
Inventory rating60 US tons

Structure

Structure typeSlab
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadUnknown
Structure length25 ft (7.7 m)
Longest span24 ft (7.2 m)
Deck width24 ft (7.2 m)
Roadway width23 ft (7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic35 (2022)
Projected traffic35 by 2043
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 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 70th ST over Drainage Ditch built?

It was built in 2018, making it 7 years old in 2025.

What condition is 70th 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 April 2022.

How much traffic does 70th ST over Drainage Ditch carry?

About 35 vehicles per day (2022 count).

How long is 70th ST over Drainage Ditch?

The structure is 25 ft (7.7 m) long with a longest span of 24 ft (7.2 m) and a deck 24 ft wide.

Who owns 70th ST over Drainage Ditch?

It is owned by the County Highway Agency.