Stockton Creek

About Stockton Creek

Stockton Creek is a dam in Mariposa, California. The dam is owned by Mariposa Public Utililty District (public utility). It impounds the Stockton Creek near Diamond Bar.

The dam stands 95 feet tall and stretches 330 feet across, creates a reservoir covering 16 acres, and has a maximum storage capacity of 368 acre-feet. Completed in 1950, 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 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 05/29/2025.

At 95 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.

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