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# San Joaquin basin

Reservoir storage across California

_Data through Aug 26, 2026 · source last checked Aug 27, 2026 · page revised Aug 27, 2026_

> Now 1.81M af, 5% below the 5-yr median.

San Joaquin basin storage fell to 1.81M af, down 6.3% from a month ago. Storage is currently running 5% below the 5-year median.

## The numbers

| Period | Current | Prior | Change |
| --- | --- | --- | --- |
| Week over week | 1.81M af | 1.82M af | -0.9% |
| Month over month | 1.81M af | 1.93M af | -6.3% |
| Year over year | 1.81M af | 1.91M af | -5.2% |
| vs 5-yr median | 1.81M af | 1.91M af | -5.2% |

## About this data

- Source: US Bureau of Reclamation RISE; California reservoirs via CA DWR CDEC
- Series: Reservoir storage summed across the basin
- Geography: San Joaquin basin
- Unit: acre-feet
- Calculation period: Daily reading
- Last observation: Aug 26, 2026
- Update frequency: Daily

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Cite: San Joaquin basin storage is 5% below its 5-yr median. The Waterline, data through Aug 26, 2026. https://the-waterline.com/basin/san-joaquin
Canonical URL: https://the-waterline.com/basin/san-joaquin