US Bridges

County RD 120A over Dimmick Creek

Fair

Douglas County, Oregon · 2.7 MI E of Sutherlin · Structure no. 19C413120A00073

Built
1967
58 years old
Condition
Fair
inspected April 2023
Type
Slab
Prestressed Concrete
Length
40 ft
1 main span
Daily traffic
674
2020 count
Owner
County
County Highway Agency

About this bridge

County RD 120A over Dimmick Creek is a prestressed concrete slab carrying County RD 120A over Dimmick Creek in Douglas County, Oregon. It was built in 1967, so it is 58 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 5 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 674 vehicles a day, roughly 3% of them trucks, projected to reach 761 by 2025. The structure is 40 ft (12.2 m) long and 28 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

Location

Open in Google Maps
CarriesCounty RD 120A
CrossesDimmick Creek
Location2.7 MI E of Sutherlin
RouteCounty Highway C120A
CountyDouglas County
StateOregon
Coordinates43.40436, -123.26583
Functional classRural Local

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.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionApril 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
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 rating69 US tons
Inventory rating33 US tons

Structure

Structure typeSlab
MaterialPrestressed Concrete
DeckOther
Main spans1
Design loadHS 20
Structure length40 ft (12.2 m)
Longest span38 ft (11.6 m)
Deck width28 ft (8.5 m)
Roadway width26 ft (7.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic674 (2020)
Projected traffic761 by 2025
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.2 mi (10 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 County RD 120A over Dimmick Creek built?

It was built in 1967, making it 58 years old in 2025.

What condition is County RD 120A over Dimmick Creek 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 April 2023.

How much traffic does County RD 120A over Dimmick Creek carry?

About 674 vehicles per day (2020 count), of which roughly 3% are trucks.

How long is County RD 120A over Dimmick Creek?

The structure is 40 ft (12.2 m) long with a longest span of 38 ft (11.6 m) and a deck 28 ft wide.

Who owns County RD 120A over Dimmick Creek?

It is owned by the County Highway Agency.