US Bridges

Interstate 505 over Cottonwood Slough

Fair

Yolo County, California · 03-YOL-505-9.66 · Structure no. 22 0115L

Built
1959
66 years old
Condition
Fair
inspected May 2023
Type
Slab
Concrete Continuous
Length
74 ft
3 main spans
Daily traffic
6,000
2010 count
Owner
State
State Highway Agency

About this bridge

Interstate 505 over Cottonwood Slough is a concrete continuous slab carrying Interstate 505 over Cottonwood Slough in Yolo County, California. It was built in 1959, so it is 66 years old, older than the California average of 54.8 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 6,000 vehicles a day, roughly 27% of them trucks, projected to reach 9,355 by 2041. The structure is 74 ft (22.7 m) long and 45 ft wide. If it were closed, the detour would be 0.6 mi (1 km).

Location

Open in Google Maps
CarriesInterstate 505
CrossesCottonwood Slough
Location03-YOL-505-9.66
RouteInterstate 505
CountyYolo County
StateCalifornia
Coordinates38.66569, -121.95188
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.
Substructure7 GoodSome minor problems.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating60.4 US tons
Inventory rating36.4 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length74 ft (22.7 m)
Longest span24 ft (7.3 m)
Deck width45 ft (13.6 m)
Roadway width42 ft (12.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic6,000 (2010)
Projected traffic9,355 by 2041
Trucks27%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed0.6 mi (1 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 Interstate 505 over Cottonwood Slough built?

It was built in 1959, making it 66 years old in 2025.

What condition is Interstate 505 over Cottonwood 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 May 2023.

How much traffic does Interstate 505 over Cottonwood Slough carry?

About 6,000 vehicles per day (2010 count), of which roughly 27% are trucks.

How long is Interstate 505 over Cottonwood Slough?

The structure is 74 ft (22.7 m) long with a longest span of 24 ft (7.3 m) and a deck 45 ft wide.

Who owns Interstate 505 over Cottonwood Slough?

It is owned by the State Highway Agency.