US Bridges

College City RD over Clarks Ditch

Poor

Colusa County, California · White Road · Structure no. 15C0100

Built
1976
49 years old
Condition
Poor
inspected October 2023
Type
Slab
Concrete Continuous
Length
63 ft
2 main spans
Daily traffic
402
2014 count
Owner
County
County Highway Agency

About this bridge

College City RD over Clarks Ditch is a concrete continuous slab carrying College City RD over Clarks Ditch in Colusa County, California. It was built in 1976, so it is 49 years old, younger than the California average of 54.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

It carries about 402 vehicles a day, roughly 10% of them trucks, projected to reach 909 by 2042. The structure is 63 ft (19.2 m) long and 32 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesCollege City RD
CrossesClarks Ditch
LocationWhite Road
RouteCounty Highway 0
CountyColusa County
StateCalifornia
Coordinates38.96943, -121.98911
Functional classRural Minor Collector

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Deck4 PoorAdvanced section loss, deterioration, spalling or scour.
Superstructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionOctober 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating29.7 US tons
Inventory rating22.8 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans2
Design loadUnknown
Structure length63 ft (19.2 m)
Longest span30 ft (9.1 m)
Deck width32 ft (9.9 m)
Roadway width32 ft (9.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic402 (2014)
Projected traffic909 by 2042
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$320,000 (2020 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was College City RD over Clarks Ditch built?

It was built in 1976, making it 49 years old in 2025.

What condition is College City RD over Clarks Ditch in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in October 2023.

How much traffic does College City RD over Clarks Ditch carry?

About 402 vehicles per day (2014 count), of which roughly 10% are trucks.

How long is College City RD over Clarks Ditch?

The structure is 63 ft (19.2 m) long with a longest span of 30 ft (9.1 m) and a deck 32 ft wide.

Who owns College City RD over Clarks Ditch?

It is owned by the County Highway Agency.