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# Colorado (Lower) basin

Reservoir storage across Arizona / California / Nevada

_Data through Aug 25, 2026 · source last checked Aug 27, 2026 · page revised Aug 27, 2026_

> Now 9.21M af, 16% below the 5-yr median.

Lower Colorado basin storage stands at 9.21M af, down 10.8% year-over-year and 16% below the 5-year median. Storage fell 0.4% on the week and 1.8% on the month.

## The numbers

| Period | Current | Prior | Change |
| --- | --- | --- | --- |
| Week over week | 9.21M af | 9.24M af | -0.4% |
| Month over month | 9.21M af | 9.37M af | -1.8% |
| Year over year | 9.21M af | 10.32M af | -10.8% |
| vs 5-yr median | 9.21M af | 10.90M af | -15.5% |

## About this data

- Source: US Bureau of Reclamation RISE; California reservoirs via CA DWR CDEC
- Series: Reservoir storage summed across the basin
- Geography: Colorado (Lower) basin
- Unit: acre-feet
- Calculation period: Daily reading
- Last observation: Aug 25, 2026
- Update frequency: Daily

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Cite: Colorado (Lower) basin storage is 16% below its 5-yr median. The Waterline, data through Aug 25, 2026. https://the-waterline.com/basin/colorado-lower
Canonical URL: https://the-waterline.com/basin/colorado-lower