US Bridges

Tennesse Sch. Road over Slough

Fair

Linn County, Oregon · 1.3 Miles East Highway 20 · Structure no. 09951 000900951

Built
1962
63 years old
Condition
Fair
inspected June 2023
Type
Slab
Prestressed Concrete
Length
45 ft
2 main spans
Daily traffic
360
2021 count
Owner
County
County Highway Agency

About this bridge

Tennesse Sch. Road over Slough is a prestressed concrete slab carrying Tennesse Sch. Road over Slough in Linn County, Oregon. It was built in 1962, so it is 63 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 360 vehicles a day, roughly 10% of them trucks, projected to reach 515 by 2041. The structure is 45 ft (13.7 m) long and 30 ft wide. If it were closed, the detour would be 2.5 mi (4 km).

Location

Open in Google Maps
CarriesTennesse Sch. Road
CrossesSlough
Location1.3 Miles East Highway 20
RouteCounty Highway A0491
CountyLinn County
StateOregon
Coordinates44.58773, -122.89843
Functional classRural Minor Collector

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 inspectionJune 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating50.7 US tons
Inventory rating38.9 US tons

Structure

Structure typeSlab
MaterialPrestressed Concrete
DeckOther
Main spans2
Design loadHS 20
Structure length45 ft (13.7 m)
Longest span22 ft (6.7 m)
Deck width30 ft (9.1 m)
Roadway width28 ft (8.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic360 (2021)
Projected traffic515 by 2041
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed2.5 mi (4 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 Tennesse Sch. Road over Slough built?

It was built in 1962, making it 63 years old in 2025.

What condition is Tennesse Sch. Road over Slough 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 June 2023.

How much traffic does Tennesse Sch. Road over Slough carry?

About 360 vehicles per day (2021 count), of which roughly 10% are trucks.

How long is Tennesse Sch. Road over Slough?

The structure is 45 ft (13.7 m) long with a longest span of 22 ft (6.7 m) and a deck 30 ft wide.

Who owns Tennesse Sch. Road over Slough?

It is owned by the County Highway Agency.