US Bridges

Fishback Road over Cooper Creek

Fair

Polk County, Oregon · 005 SW of State HWY 51 · Structure no. 53C104851000171

Built
1965
60 years old
Condition
Fair
inspected August 2024
Type
Slab
Prestressed Concrete
Length
29 ft
1 main span
Daily traffic
106
2020 count
Owner
County
County Highway Agency

About this bridge

Fishback Road over Cooper Creek is a prestressed concrete slab carrying Fishback Road over Cooper Creek in Polk County, Oregon. It was built in 1965, so it is 60 years old, older than the Oregon average of 49.9 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 106 vehicles a day, projected to reach 152 by 2040. The structure is 29 ft (8.8 m) long and 24 ft wide. If it were closed, the detour would be 9.3 mi (15 km).

Location

Open in Google Maps
CarriesFishback Road
CrossesCooper Creek
Location005 SW of State HWY 51
RouteCounty Highway 0
CountyPolk County
StateOregon
Coordinates44.83479, -123.32853
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
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionAugust 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation6: Equal to present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating63.1 US tons
Inventory rating38 US tons

Structure

Structure typeSlab
MaterialPrestressed Concrete
DeckOther
Main spans1
Design loadHS 20
Structure length29 ft (8.8 m)
Longest span27 ft (8.2 m)
Deck width24 ft (7.3 m)
Roadway width23 ft (6.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic106 (2020)
Projected traffic152 by 2040
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed9.3 mi (15 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty 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 Fishback Road over Cooper Creek built?

It was built in 1965, making it 60 years old in 2025.

What condition is Fishback Road over Cooper 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 August 2024.

How much traffic does Fishback Road over Cooper Creek carry?

About 106 vehicles per day (2020 count).

How long is Fishback Road over Cooper Creek?

The structure is 29 ft (8.8 m) long with a longest span of 27 ft (8.2 m) and a deck 24 ft wide.

Who owns Fishback Road over Cooper Creek?

It is owned by the County Highway Agency.