Basins
Near normalSan Joaquin basin
Reservoir storage across California
Data through Aug 26, 2026 · source last checked Aug 27, 2026 · page revised Aug 27, 2026
Cite
- Millerton Lake
- New Melones Lake
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
- Daily reading
- Last observation
- Aug 26, 2026
- Update frequency
- Daily
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.
| 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% |
Previous weeks
Week of Aug 19, 2026
San Joaquin basin storage dropped to 1.82M af, down 1.7% on the week. Month over month, storage fell 7.5% from 1.97M af. The basin is 6% below the 5-year median.
An earlier week
San Joaquin basin storage fell to 1.86M af, down 8.0% over the past month and 6% below the 5-year median. Year over year, the basin is down 5.7%.
Week of Aug 13, 2026
San Joaquin basin storage fell to 1.87M af, down 1.3% on the week. The basin is 6% below its 5-year median. Month-over-month storage declined 8.4%, tracking the ongoing summer drawdown.