US Bridges

710th Ave over Hardin-Story Dd I

Fair

Story County, Iowa · 085210304 · Structure no. 000000000315700

Built
1947
78 years old
Condition
Fair
inspected November 2022
Type
Stringer/Multi-beam or Girder
Steel
Length
31 ft
1 main span
Daily traffic
60
2022 count
Owner
County
County Highway Agency

About this bridge

710th Ave over Hardin-Story Dd I is a steel stringer/multi-beam or girder carrying 710th Ave over Hardin-Story Dd I in Story County, Iowa. It was built in 1947, so it is 78 years old, older 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 60 vehicles a day, projected to reach 60 by 2043. The structure is 31 ft (9.4 m) long and 20 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
Carries710th Ave
CrossesHardin-Story Dd I
Location085210304
RouteCounty Highway 0
CountyStory County
StateIowa
Coordinates42.20107, -93.29011
Functional classRural Local

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionNovember 2022
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating48.9 US tons
Inventory rating30 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckWood or timber
Main spans1
Design loadUnknown
Structure length31 ft (9.4 m)
Longest span28 ft (8.5 m)
Deck width20 ft (6.1 m)
Roadway width19 ft (5.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic60 (2022)
Projected traffic60 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 proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was 710th Ave over Hardin-Story Dd I built?

It was built in 1947, making it 78 years old in 2025.

What condition is 710th Ave over Hardin-Story Dd I 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 November 2022.

How much traffic does 710th Ave over Hardin-Story Dd I carry?

About 60 vehicles per day (2022 count).

How long is 710th Ave over Hardin-Story Dd I?

The structure is 31 ft (9.4 m) long with a longest span of 28 ft (8.5 m) and a deck 20 ft wide.

Who owns 710th Ave over Hardin-Story Dd I?

It is owned by the County Highway Agency.