US Bridges

US101 (hwy 9) over Hoquarten Slough

Good

Tillamook County, Oregon · In Tillamook · Structure no. 22364 009 06555

Built
2018
7 years old
Condition
Good
inspected March 2024
Type
Box Beam or Girders - Multiple
Prestressed Concrete
Length
150 ft
3 main spans
Daily traffic
10,249
2022 count
Owner
State
State Highway Agency

About this bridge

US101 (hwy 9) over Hoquarten Slough is a prestressed concrete box beam or girders - multiple carrying US101 (hwy 9) over Hoquarten Slough in Tillamook County, Oregon. It was built in 2018, so it is 7 years old, younger than the Oregon average of 49.9 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 10,249 vehicles a day, roughly 22% of them trucks, projected to reach 10,500 by 2042. The structure is 150 ft (45.7 m) long and 82 ft wide. If it were closed, the detour would be 55.9 mi (90 km).

Location

Open in Google Maps
CarriesUS101 (hwy 9)
CrossesHoquarten Slough
LocationIn Tillamook
RouteU.S. Route 101
CountyTillamook County
StateOregon
Coordinates45.45911, -123.84411
Functional classRural Principal Arterial - Other

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionMarch 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation7: Better than 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 rating45 US tons
Inventory rating34.6 US tons

Structure

Structure typeBox Beam or Girders - Multiple
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans3
Design loadHL 93
Structure length150 ft (45.7 m)
Longest span69 ft (21 m)
Deck width82 ft (24.9 m)
Roadway width60 ft (18.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic10,249 (2022)
Projected traffic10,500 by 2042
Trucks22%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed55.9 mi (90 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 Hoquarten Slough built?

It was built in 2018, making it 7 years old in 2025.

What condition is US101 (hwy 9) over Hoquarten Slough in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in March 2024.

How much traffic does US101 (hwy 9) over Hoquarten Slough carry?

About 10,249 vehicles per day (2022 count), of which roughly 22% are trucks.

How long is US101 (hwy 9) over Hoquarten Slough?

The structure is 150 ft (45.7 m) long with a longest span of 69 ft (21 m) and a deck 82 ft wide.

Who owns US101 (hwy 9) over Hoquarten Slough?

It is owned by the State Highway Agency.