Reservoirs
Above normalSan Luis Reservoir water level
Live reservoir storage and water level in San Joaquin-Delta basin, California
Data through Oct 15, 2026 · source last checked Oct 17, 2026 · page revised Oct 16, 2026
Cite
- Storage
About this data
- Source
- US Bureau of Reclamation RISE; California reservoirs via CA DWR CDEC
- Series
- End-of-day reservoir storage
- Geography
- San Luis Reservoir water level
- Unit
- acre-feet
- Calculation
- Daily reading
- Last observation
- Oct 15, 2026
- Update frequency
- Daily
Now 1.46M af, 38% above the 5-yr median, 71% of capacity.
San Luis storage stands at 1.46M af, 38% above the 5-year median and 71% of capacity. The reservoir dropped 2.3% on the week but has risen 4.4% month-over-month and 34.6% year-over-year.
| Period | Current | Prior | Change |
|---|---|---|---|
| Week over week | 1.46M af | 1.49M af | -2.3% |
| Month over month | 1.46M af | 1.39M af | +4.4% |
| Year over year | 1.46M af | 1.08M af | +34.6% |
| vs 5-yr median | 1.46M af | 1.05M af | +38.1% |
| Measure | Value |
|---|---|
| Latest reading, Oct 15, 2026 | 495.55 ft above sea level |
| Change from a week earlier | -2.96 ft |
| Change from a year earlier | +34.63 ft |
| 5-yr median for the date | 458.23 ft |
| Below full pool | 48.45 ft |
| Five-year low | 350.95 ft (Oct 23, 2021) |
| Five-year high | 543.04 ft (Apr 6, 2023) |
| Measure | Value | Source |
|---|---|---|
| Full pool elevation | 544 ft above sea level (top of active conservation pool) | USBR |
| Maximum depth at the dam | 303 ft | USBR |
| Surface area at full pool | 13,000 acres | CDEC |
| Total capacity | 2,041,000 acre-feet | CDEC |
Previous weeks
Week of Oct 7, 2026
San Luis Reservoir stands at 1.46M af, 38% above the five-year median as of this week, per Bureau of Reclamation. Storage is down 2% on the week but remains well above the seasonal median heading into WY2027.
Week of Sep 23, 2026
San Luis Reservoir entered water year 2027 at 1.47M af on October 1, 2026, up 3% on the week and 45% above its five-year median (Bureau of Reclamation). As California's primary south-of-Delta off-stream storage, the reservoir serves both CVP and SWP contractors. Storage is tracking well above the five-year seasonal norm heading into the new water year.
About San Luis Reservoir
San Luis Reservoir's water level is 495.55 feet above sea level as of Oct 15, 2026, 48.45 feet below full pool (544 feet), with 1.46 million acre-feet in storage (71% of capacity). That is 2.96 feet lower than a week earlier and 34.63 feet higher than a year earlier.
San Luis Reservoir is an off-stream basin behind B.F. Sisk Dam, filled by pumping rather than by a river of its own, and the largest off-stream reservoir in the country. Reclamation owns the dam and the California Department of Water Resources operates it, with the storage split about 55 percent state and 45 percent federal. In wet months, Delta water arriving down the California Aqueduct and the Delta-Mendota Canal is pumped up from O'Neill Forebay and held for release to farms and cities to the south later in the year.
Total capacity is 2.04M af, over the past five years storage has ranged from 192,050 af to 2.03M af.
San Luis Reservoir is one of the 21 major reservoirs this site totals each day. For the combined picture, western reservoir levels carries the storage of all 21 on one chart, which is the number to watch when the question is about the West as a whole rather than about this project.
Those figures describe the reservoir at full pool, not today. The chart at the top of this page tracks storage in acre-feet and the elevation table tracks the water surface in feet, so read storage against total capacity for how full the reservoir is, and the elevation against the full pool elevation and maximum depth for the size of the water column behind the dam. The two do not move together one for one: a reservoir narrows as it deepens, so one holding half its capacity still stands more than half as deep.
Sources: full pool elevation and maximum depth from the Bureau of Reclamation; surface area and total capacity from the California Data Exchange Center.
Because pumps fill it on the two projects' schedule, the level follows a yearly cycle rather than a river's: over 1991-2020 storage averaged highest in March and lowest in August, per the California Data Exchange Center. Why the San Luis Reservoir level swings walks through that cycle, the federal and state shares, and five years of readings.