US Bridges

US101 (hwy 9) over Skipanon River

Fair

Clatsop County, Oregon · 08.73 S Astoria · Structure no. 08317 009 00873

Built
1980
45 years old
Condition
Fair
inspected October 2023
Type
Slab
Prestressed Concrete
Length
96 ft
3 main spans
Daily traffic
16,106
2022 count
Owner
State
State Highway Agency

About this bridge

US101 (hwy 9) over Skipanon River is a prestressed concrete slab carrying US101 (hwy 9) over Skipanon River in Clatsop County, Oregon. It was built in 1980, so it is 45 years old, younger 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 16,106 vehicles a day, roughly 4% of them trucks, projected to reach 17,300 by 2042. The structure is 96 ft (29.3 m) long and 44 ft wide. If it were closed, the detour would be 39.8 mi (64 km).

Location

Open in Google Maps
CarriesUS101 (hwy 9)
CrossesSkipanon River
Location08.73 S Astoria
RouteU.S. Route 101
CountyClatsop County
StateOregon
Coordinates46.13861, -123.92447
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.
Substructure8 Very GoodNo problems noted.
Channel and channel protection7 GoodSome minor problems.
Last inspectionOctober 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; action required to protect exposed foundations
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating55 US tons
Inventory rating42.5 US tons

Structure

Structure typeSlab
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans3
Design loadHS 20
Structure length96 ft (29.3 m)
Longest span32 ft (9.8 m)
Deck width44 ft (13.4 m)
Roadway width41 ft (12.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic16,106 (2022)
Projected traffic17,300 by 2042
Trucks4%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed39.8 mi (64 km)
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkNon-Interstate STRAHNET route

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 US101 (hwy 9) over Skipanon River built?

It was built in 1980, making it 45 years old in 2025.

What condition is US101 (hwy 9) over Skipanon 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 October 2023.

How much traffic does US101 (hwy 9) over Skipanon River carry?

About 16,106 vehicles per day (2022 count), of which roughly 4% are trucks.

How long is US101 (hwy 9) over Skipanon River?

The structure is 96 ft (29.3 m) long with a longest span of 32 ft (9.8 m) and a deck 44 ft wide.

Who owns US101 (hwy 9) over Skipanon River?

It is owned by the State Highway Agency.