Calero
Calero is an earth dam located in Santa Clara County, California, built in 1935. It carries a High hazard potential classification and has a poor condition assessment.
About Calero
The primary purpose of Calero 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 Santa Clara Valley Water District (public utility). It impounds the Calero Creek near San Jose.
The dam stands 90 feet tall and stretches 840 feet across, creates a reservoir covering 337 acres, has a maximum storage capacity of 9,850 acre-feet, and collects water from a drainage area of 7 square miles. Completed in 1935, the structure is well-established, with more than 75 years of service.
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 poor, meaning the dam has recognized safety deficiencies that require remediation to address risks. An emergency action plan is in place for this dam. The most recent inspection on record was 11/19/2025.
At 90 feet, this dam is taller than 98% 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.
Location
| State | California |
| County | Santa Clara |
| Nearest City | San Jose |
| River/Stream | Calero Creek |
| Coordinates | 37.18360, -121.79130 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 90 ft |
| Dam Height | 90 ft |
| Dam Length | 840 ft |
| Year Completed | 1935 (91 years old) |
Storage & Hydraulics
| NID Storage | 9,850 acre-ft |
| Max Storage | 9,850 acre-ft |
| Surface Area | 337 acres |
| Drainage Area | 7 sq mi |
Ownership & Safety
| Purpose | Water Supply |
| Owner | Santa Clara Valley Water District |
| Owner Type | Public Utility |
| Hazard Classification | High |
| Condition Assessment | Poor |
| Last Inspection | 11/19/2025 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | CA00288 |
| Federal ID | CA00288 |
| More Info | State Dam Safety Program |