US Bridges

Ia 1 over English River

Fair

Washington County, Iowa · 1.1 Mi. S of Jct. Ia 22 · Structure no. 000000000051671

Built
1979
46 years old
Condition
Fair
inspected March 2024
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
347 ft
4 main spans
Daily traffic
4,120
2022 count
Owner
State
State Highway Agency

About this bridge

Ia 1 over English River is a prestressed concrete stringer/multi-beam or girder carrying Ia 1 over English River in Washington County, Iowa. It was built in 1979, so it is 46 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 4,120 vehicles a day, roughly 10% of them trucks, projected to reach 4,120 by 2044. The structure is 347 ft (105.8 m) long and 47 ft wide. If it were closed, the detour would be 14.3 mi (23 km).

Location

Open in Google Maps
CarriesIa 1
CrossesEnglish River
Location1.1 Mi. S of Jct. Ia 22
RouteState Highway 1
CountyWashington County
StateIowa
Coordinates41.46927, -91.71455
Functional classRural Principal Arterial - Other

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure7 GoodSome minor problems.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMarch 2024
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 geometry7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating80.4 US tons
Inventory rating35.9 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20
Structure length347 ft (105.8 m)
Longest span97 ft (29.6 m)
Deck width47 ft (14.4 m)
Roadway width44 ft (13.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic4,120 (2022)
Projected traffic4,120 by 2044
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed14.3 mi (23 km)
TollOn a free road
National Highway SystemYes

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—
NavigationNo navigation control on waterway

Frequently asked questions

When was Ia 1 over English River built?

It was built in 1979, making it 46 years old in 2025.

What condition is Ia 1 over English River 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 March 2024.

How much traffic does Ia 1 over English River carry?

About 4,120 vehicles per day (2022 count), of which roughly 10% are trucks.

How long is Ia 1 over English River?

The structure is 347 ft (105.8 m) long with a longest span of 97 ft (29.6 m) and a deck 47 ft wide.

Who owns Ia 1 over English River?

It is owned by the State Highway Agency.