US Bridges

Ia 4 over Drainage Ditch

Fair

Palo Alto County, Iowa · 1.3 Mi. S of SR B57 · Structure no. 000000000039200

Built
1918
107 years old, rebuilt 1959
Condition
Fair
inspected August 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
24 ft
1 main span
Daily traffic
2,040
2022 count
Owner
State
State Highway Agency

About this bridge

Ia 4 over Drainage Ditch is a steel stringer/multi-beam or girder carrying Ia 4 over Drainage Ditch in Palo Alto County, Iowa. It was built in 1918 and reconstructed in 1959, so it is 107 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 5 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 2,040 vehicles a day, roughly 19% of them trucks, projected to reach 2,040 by 2043. The structure is 24 ft (7.3 m) long and 34 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

Location

Open in Google Maps
CarriesIa 4
CrossesDrainage Ditch
Location1.3 Mi. S of SR B57
RouteState Highway 4
CountyPalo Alto County
StateIowa
Coordinates42.96114, -94.67856
Functional classRural Minor Arterial

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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating51.5 US tons
Inventory rating31.7 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadH 15
Structure length24 ft (7.3 m)
Longest span22 ft (6.7 m)
Deck width34 ft (10.5 m)
Roadway width31 ft (9.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,040 (2022)
Projected traffic2,040 by 2043
Trucks19%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.2 mi (10 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusPossibly eligible for the National Register; requires further investigation
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Ia 4 over Drainage Ditch built?

It was built in 1918, making it 107 years old in 2025. It was reconstructed in 1959.

What condition is Ia 4 over Drainage Ditch 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 August 2023.

How much traffic does Ia 4 over Drainage Ditch carry?

About 2,040 vehicles per day (2022 count), of which roughly 19% are trucks.

How long is Ia 4 over Drainage Ditch?

The structure is 24 ft (7.3 m) long with a longest span of 22 ft (6.7 m) and a deck 34 ft wide.

Who owns Ia 4 over Drainage Ditch?

It is owned by the State Highway Agency.