US Bridges

I-5 (hwy 1) SB over Santiam Overflow No. 4

Fair

Linn County, Oregon · 06.2 MI N of Albany Ncl · Structure no. 08124 001 24042

Built
1958
67 years old, rebuilt 1992
Condition
Fair
inspected February 2023
Type
Tee Beam
Concrete Continuous
Length
170 ft
5 main spans
Daily traffic
33,446
2022 count
Owner
State
State Highway Agency

About this bridge

I-5 (hwy 1) SB over Santiam Overflow No. 4 is a concrete continuous tee beam carrying I-5 (hwy 1) SB over Santiam Overflow No. 4 in Linn County, Oregon. It was built in 1958 and reconstructed in 1992, 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.

It carries about 33,446 vehicles a day, roughly 15% of them trucks, projected to reach 36,150 by 2042. The structure is 170 ft (51.8 m) long and 67 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

CarriesI-5 (hwy 1) SB
CrossesSantiam Overflow No. 4
Location06.2 MI N of Albany Ncl
RouteInterstate 5
StateOregon
Coordinates44.73343, -123.0533
Functional classRural Principal Arterial - Interstate

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 inspectionFebruary 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation6: Equal to present minimum criteria
Deck geometry9: Superior to present desirable criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating56 US tons
Inventory rating34 US tons

Structure

Structure typeTee Beam
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans5
Design loadHS 20
Structure length170 ft (51.8 m)
Longest span36 ft (11 m)
Deck width67 ft (20.5 m)
Roadway width63 ft (19.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic33,446 (2022)
Projected traffic36,150 by 2042
Trucks15%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesRelief for waterway
Detour if closed1.9 mi (3 km)
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate 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 I-5 (hwy 1) SB over Santiam Overflow No. 4 built?

It was built in 1958, making it 67 years old in 2025. It was reconstructed in 1992.

What condition is I-5 (hwy 1) SB over Santiam Overflow No. 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 February 2023.

How much traffic does I-5 (hwy 1) SB over Santiam Overflow No. 4 carry?

About 33,446 vehicles per day (2022 count), of which roughly 15% are trucks.

How long is I-5 (hwy 1) SB over Santiam Overflow No. 4?

The structure is 170 ft (51.8 m) long with a longest span of 36 ft (11 m) and a deck 67 ft wide.

Who owns I-5 (hwy 1) SB over Santiam Overflow No. 4?

It is owned by the State Highway Agency.