US Bridges

EB US 20 over Buffalo Creek

Fair

Buchanan County, Iowa · 2.3 Mi. E of Jct. SR W40 · Structure no. 000000000603660

Built
1978
47 years old
Condition
Fair
inspected November 2024
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
305 ft
4 main spans
Daily traffic
3,500
2022 count
Owner
State
State Highway Agency

About this bridge

EB US 20 over Buffalo Creek is a prestressed concrete stringer/multi-beam or girder carrying EB US 20 over Buffalo Creek in Buchanan County, Iowa. It was built in 1978, so it is 47 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 3,500 vehicles a day, roughly 30% of them trucks, projected to reach 3,500 by 2044. The structure is 305 ft (93 m) long and 44 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesEB US 20
CrossesBuffalo Creek
Location2.3 Mi. E of Jct. SR W40
RouteU.S. Route 20
CountyBuchanan County
StateIowa
Coordinates42.46056, -91.70895
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionNovember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating73.4 US tons
Inventory rating50.5 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20
Structure length305 ft (93 m)
Longest span82 ft (25 m)
Deck width44 ft (13.3 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic3,500 (2022)
Projected traffic3,500 by 2044
Trucks30%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 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 EB US 20 over Buffalo Creek built?

It was built in 1978, making it 47 years old in 2025.

What condition is EB US 20 over Buffalo Creek 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 2024.

How much traffic does EB US 20 over Buffalo Creek carry?

About 3,500 vehicles per day (2022 count), of which roughly 30% are trucks.

How long is EB US 20 over Buffalo Creek?

The structure is 305 ft (93 m) long with a longest span of 82 ft (25 m) and a deck 44 ft wide.

Who owns EB US 20 over Buffalo Creek?

It is owned by the State Highway Agency.