Reservoir · California · United States · CDEC
CASTAIC
95.5% full
Capacity
399.28 hm³
Volume stored
382 hm³
Coordinates
34.515°N, 118.610°W
Last updated
2026-09-17
Current fill
95.5%vs 7 days ago
+0.7%gaining
vs 1 year ago
+10.2%year-over-year
7-day trend
→stable
Data source: CDEC — California Dept of Water Resources — daily reservoir storage volume. Capacity is the design (normal full-pool) capacity from the US National Inventory of Dams (NID); fill % = current volume ÷ design capacity. Last reading: 2026-09-17.
Catchment Weather
Past 30 days + 14-day forecast · Open-Meteo
Satellite imagery: Esri, Maxar, Earthstar Geographics. Map: Esri, HERE, Garmin, © OpenStreetMap contributors. 34.515, -118.610 · Open in Google Maps
About CASTAIC
As of September 17, 2026, CASTAIC is filled to 95.5% of its total capacity, holding roughly 382 hm³ of water out of a maximum 399 hm³. At this level the reservoir is high.
Over the most recent week on record the fill level has held broadly steady (+0.7 pts), and it is 10.2 points above its level on the same date a year earlier.
Across the readings we hold for CASTAIC — 1823 data points between September 19, 2021 and September 17, 2026 — the level has ranged from a low of 27.0% (September 21, 2021) to a high of 100.2% (July 12, 2023). On average the reservoir is fullest around June and at its lowest around December.
It is operated by CDEC primarily for multiple purposes. It lies within the California basin at 34.515°N, 118.610°W.
Key facts
- Current fill level
- 95.5%
- Water stored
- 382 hm³
- Total capacity
- 399 hm³
- 7-day change
- ▲ 0.7 pts
- Year-on-year
- ▲ 10.2 pts
- Primary use
- Multipurpose
- River basin
- California
- Operator
- CDEC
- Coordinates
- 34.515°N, 118.610°W
- Last updated
- September 17, 2026
Recent readings
| Date | Fill level | Volume (hm³) |
|---|---|---|
| 17 Sep 2026 | 95.5% | 381 |
| 16 Sep 2026 | 95.0% | 379 |
| 15 Sep 2026 | 94.7% | 378 |
| 14 Sep 2026 | 95.0% | 379 |
| 13 Sep 2026 | 95.3% | 380 |
| 12 Sep 2026 | 95.5% | 381 |
| 11 Sep 2026 | 95.3% | 380 |
| 10 Sep 2026 | 94.8% | 379 |
| 9 Sep 2026 | 94.1% | 376 |
| 8 Sep 2026 | 93.8% | 374 |
| 7 Sep 2026 | 94.1% | 376 |
| 6 Sep 2026 | 94.3% | 377 |