US Bridges

D 65 310th ST over I-29

Fair

Woodbury County, Iowa · 2.2 Mi. N of Jct. Ia 141 · Structure no. 000000000053630

Built
1959
66 years old
Condition
Fair
inspected December 2024
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
235 ft
4 main spans
Daily traffic
90
2022 count
Owner
State
State Highway Agency

About this bridge

D 65 310th ST over I-29 is a prestressed concrete stringer/multi-beam or girder carrying D 65 310th ST over I-29 in Woodbury County, Iowa. It was built in 1959, so it is 66 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 90 vehicles a day, projected to reach 90 by 2044. The structure is 235 ft (71.6 m) long and 28 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesD 65 310th ST
CrossesI-29
Location2.2 Mi. N of Jct. Ia 141
RouteCounty Highway 0
CountyWoodbury County
StateIowa
Coordinates42.2578, -96.259
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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Last inspectionDecember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating53.2 US tons
Inventory rating15.5 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans4
Design loadH 15
Structure length235 ft (71.6 m)
Longest span70 ft (21.3 m)
Deck width28 ft (8.6 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic90 (2022)
Projected traffic90 by 2044
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed1.9 mi (3 km)
TollOn a free road
National Highway SystemNo

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 D 65 310th ST over I-29 built?

It was built in 1959, making it 66 years old in 2025.

What condition is D 65 310th ST over I-29 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 December 2024.

How much traffic does D 65 310th ST over I-29 carry?

About 90 vehicles per day (2022 count).

How long is D 65 310th ST over I-29?

The structure is 235 ft (71.6 m) long with a longest span of 70 ft (21.3 m) and a deck 28 ft wide.

Who owns D 65 310th ST over I-29?

It is owned by the State Highway Agency.