US Bridges

Ia 13 over US 20

Fair

Delaware County, Iowa · At Jct. US 20 · Structure no. 000000000023250

Built
1970
55 years old
Condition
Fair
inspected September 2024
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
262 ft
4 main spans
Daily traffic
6,400
2022 count
Owner
State
State Highway Agency

About this bridge

Ia 13 over US 20 is a prestressed concrete stringer/multi-beam or girder carrying Ia 13 over US 20 in Delaware County, Iowa. It was built in 1970, so it is 55 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 6,400 vehicles a day, roughly 14% of them trucks, projected to reach 6,400 by 2044. The structure is 262 ft (79.9 m) long and 47 ft wide. If it were closed, the detour would be 8.1 mi (13 km).

Location

Open in Google Maps
CarriesIa 13
CrossesUS 20
LocationAt Jct. US 20
RouteState Highway 13
CountyDelaware County
StateIowa
Coordinates42.46385, -91.48079
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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation8: Equal to present desirable criteria
Deck geometry6: Equal to present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating95.9 US tons
Inventory rating57.4 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20
Structure length262 ft (79.9 m)
Longest span86 ft (26.2 m)
Deck width47 ft (14.4 m)
Roadway width44 ft (13.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic6,400 (2022)
Projected traffic6,400 by 2044
Trucks14%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesOverpass structure at an interchange
CrossesHighway
Detour if closed8.1 mi (13 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—
NavigationNot applicable (no waterway)

Frequently asked questions

When was Ia 13 over US 20 built?

It was built in 1970, making it 55 years old in 2025.

What condition is Ia 13 over US 20 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 September 2024.

How much traffic does Ia 13 over US 20 carry?

About 6,400 vehicles per day (2022 count), of which roughly 14% are trucks.

How long is Ia 13 over US 20?

The structure is 262 ft (79.9 m) long with a longest span of 86 ft (26.2 m) and a deck 47 ft wide.

Who owns Ia 13 over US 20?

It is owned by the State Highway Agency.