New Calaveras

New Calaveras is an earth dam located in Alameda County, California, built in 2018. It carries a High hazard potential classification and has a satisfactory condition assessment.

About New Calaveras

The primary purpose of New Calaveras 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 City And County Of San Francisco (local government). It impounds the Calaveras Creek near Fremont.

The dam stands 210 feet tall and stretches 1,210 feet across, creates a reservoir covering 1,435 acres, has a maximum storage capacity of 96,850 acre-feet, and collects water from a drainage area of 98 square miles. Completed in 2018, the structure is relatively new.

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 06/04/2025.

At 210 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
CountyAlameda
Nearest CityFremont
River/StreamCalaveras Creek
Coordinates37.49520, -121.81780

Physical Characteristics

Dam TypeEarth
NID Height210 ft
Dam Height210 ft
Dam Length1,210 ft
Year Completed2018 (8 years old)

Storage & Hydraulics

NID Storage96,850 acre-ft
Max Storage96,850 acre-ft
Surface Area1,435 acres
Drainage Area98 sq mi

Ownership & Safety

PurposeWater Supply
OwnerCity and County of San Francisco
Owner TypeLocal Government
Hazard ClassificationHigh
Condition AssessmentSatisfactory
Last Inspection06/04/2025
Emergency Action PlanYes

Identifiers

NID IDCA01546
Federal IDCA01546
More InfoState Dam Safety Program

Nearby Dams