Los Vaqueros

Los Vaqueros is an earth dam located in Contra Costa County, California, built in 1997. It carries a High hazard potential classification and has a satisfactory condition assessment.

About Los Vaqueros

The primary purpose of Los Vaqueros is water supply. The dam stores water for municipal, industrial, or agricultural use, helping ensure a reliable supply for the surrounding area. The dam is owned by Contra Costa Water District (public utility). It impounds the Kellogg Creek near Byron, Brentwood, Discovery Bay.

The dam stands 231 feet tall and stretches 1,280 feet across, creates a reservoir covering 1,836 acres, has a maximum storage capacity of 160,000 acre-feet, and collects water from a drainage area of 18 square miles. Completed in 1997, the structure is 29 years old.

This dam carries a high hazard potential classification, which means that a failure or uncontrolled release of water would likely cause loss of human life. This classification reflects the consequences of failure, not the likelihood — it indicates that people live or work in the area downstream. Its condition is rated satisfactory, indicating no existing or potential dam safety deficiencies are recognized. An emergency action plan is in place for this dam. The most recent inspection on record was 10/09/2024.

At 231 feet, this dam is taller than 99% of all dams in the United States.

Living Downstream

If you live or work downstream of this dam, consider taking these steps: learn your local evacuation routes, check whether your county emergency management office has a dam failure inundation map, and sign up for local emergency alerts. The California dam safety program can provide more specific information about emergency planning for this structure.

Search for dams near your address to see all dams in your area with hazard classifications and safety data.

High HazardSatisfactory ConditionEmergency Action Plan: Yes

Location

StateCalifornia
CountyContra Costa
Nearest CityByron, Brentwood, Discovery Bay
River/StreamKellogg Creek
Coordinates37.83630, -121.72650

Physical Characteristics

Dam TypeEarth
NID Height231 ft
Dam Height231 ft
Dam Length1,280 ft
Year Completed1997 (29 years old)

Storage & Hydraulics

NID Storage160,000 acre-ft
Max Storage160,000 acre-ft
Surface Area1,836 acres
Drainage Area18 sq mi

Ownership & Safety

PurposeWater Supply
OwnerContra Costa Water District
Owner TypePublic Utility
Hazard ClassificationHigh
Condition AssessmentSatisfactory
Last Inspection10/09/2024
Emergency Action PlanYes

Identifiers

NID IDCA01396
Federal IDCA01396
More InfoState Dam Safety Program

Nearby Dams