US Bridges

Chestnut Ave over Colma Canal

Fair

San Mateo County, California · 0.1 MI S Commercial Ave · Structure no. 35C0079

Built
1976
49 years old
Condition
Fair
inspected April 2023
Type
Culvert
Concrete Continuous
Length
40 ft
3 main spans
Daily traffic
23,265
2010 count
Owner
City
City or Municipal Highway Agency

About this bridge

Chestnut Ave over Colma Canal is a concrete continuous culvert carrying Chestnut Ave over Colma Canal in San Mateo 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 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 23,265 vehicles a day, roughly 15% of them trucks, projected to reach 23,734 by 2041. The structure is 40 ft (12.2 m) long and 91 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

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CarriesChestnut Ave
CrossesColma Canal
Location0.1 MI S Commercial Ave
RouteCity Street 0
CountySan Mateo County
StateCalifornia
Coordinates37.65625, -122.43219
Functional classUrban Minor Arterial

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Channel and channel protection8 Very GoodNo problems noted.
Culvert6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionApril 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating59.6 US tons
Inventory rating35.7 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadUnknown
Structure length40 ft (12.2 m)
Longest span13 ft (4 m)
Deck width91 ft (27.7 m)
Roadway width74 ft (22.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic23,265 (2010)
Projected traffic23,734 by 2041
Trucks15%
Lanes on structure5
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed1.9 mi (3 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCity or Municipal Highway Agency
Maintained byCity or Municipal Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Chestnut Ave over Colma Canal built?

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

What condition is Chestnut Ave over Colma Canal 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 Chestnut Ave over Colma Canal carry?

About 23,265 vehicles per day (2010 count), of which roughly 15% are trucks.

How long is Chestnut Ave over Colma Canal?

The structure is 40 ft (12.2 m) long with a longest span of 13 ft (4 m) and a deck 91 ft wide.

Who owns Chestnut Ave over Colma Canal?

It is owned by the City or Municipal Highway Agency.