US Bridges

HWY 164 over Santiam River Oflow #4

FairPosted for load

Linn County, Oregon · 009 MI E Linn Marion CO L · Structure no. 00361 164 00712

Built
1958
67 years old
Condition
Fair
inspected July 2023
Type
Channel Beam
Concrete
Length
294 ft
14 main spans
Daily traffic
7,541
2022 count
Owner
State
State Highway Agency

About this bridge

HWY 164 over Santiam River Oflow #4 is a concrete channel beam carrying HWY 164 over Santiam River Oflow #4 in Linn County, Oregon. It was built in 1958, so it is 67 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. Its operating status is: posted for other load-capacity restriction.

It carries about 7,541 vehicles a day, roughly 9% of them trucks, projected to reach 10,200 by 2042. The structure is 294 ft (89.6 m) long and 29 ft wide. If it were closed, the detour would be 8.1 mi (13 km).

Location

Open in Google Maps
CarriesHWY 164
CrossesSantiam River Oflow #4
Location009 MI E Linn Marion CO L
RouteState Highway 164
CountyLinn County
StateOregon
Coordinates44.71004, -123.03041
Functional classRural Minor Arterial

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 inspectionJuly 2023
Inspection intervalevery 24 months
Operating statusPosted for other load-capacity restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating31.7 US tons
Inventory rating24.7 US tons

Structure

Structure typeChannel Beam
MaterialConcrete
DeckConcrete, precast panels
Main spans14
Design loadHS 20
Structure length294 ft (89.6 m)
Longest span21 ft (6.4 m)
Deck width29 ft (8.8 m)
Roadway width26 ft (7.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic7,541 (2022)
Projected traffic10,200 by 2042
Trucks9%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesRelief for waterway
Detour if closed8.1 mi (13 km)
TollOn a free road
National Highway SystemNo

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 HWY 164 over Santiam River Oflow #4 built?

It was built in 1958, making it 67 years old in 2025.

What condition is HWY 164 over Santiam River Oflow #4 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 July 2023.

How much traffic does HWY 164 over Santiam River Oflow #4 carry?

About 7,541 vehicles per day (2022 count), of which roughly 9% are trucks.

How long is HWY 164 over Santiam River Oflow #4?

The structure is 294 ft (89.6 m) long with a longest span of 21 ft (6.4 m) and a deck 29 ft wide.

Who owns HWY 164 over Santiam River Oflow #4?

It is owned by the State Highway Agency.