Reservoir · California · United States · CDEC
Lake McSwain
105.0% full
Capacity
10.18 hm³
Volume stored
11 hm³
Coordinates
37.520°N, 120.309°W
Last updated
2026-08-02
Current fill
105.0%vs 7 days ago
0.0%stable
vs 1 year ago
+0.3%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: 2026-08-02.
Catchment Weather
Past 30 days + 14-day forecast · Open-Meteo
Satellite imagery: Esri, Maxar, Earthstar Geographics. Map: Esri, HERE, Garmin, © OpenStreetMap contributors. 37.520, -120.309 · Open in Google Maps
About Lake McSwain
As of August 2, 2026, Lake McSwain is filled to 105.0% of its total capacity, holding roughly 11 hm³ of water out of a maximum 10 hm³. At this level the reservoir is effectively full.
Over the most recent week on record the fill level has held broadly steady (+0.0 pts), and it sits close to where it was a year earlier.
Across the readings we hold for Lake McSwain — 1810 data points between August 5, 2021 and August 2, 2026 — the level has ranged from a low of 69.7% (December 1, 2025) to a high of 105.0% (August 5, 2021). On average the reservoir is fullest around September and at its lowest around November.
It is operated by CDEC primarily for multiple purposes. It lies within the California basin at 37.520°N, 120.309°W.
Key facts
- Current fill level
- 105.0%
- Water stored
- 11 hm³
- Total capacity
- 10 hm³
- 7-day change
- No change
- Year-on-year
- ▲ 0.3 pts
- Primary use
- Multipurpose
- River basin
- California
- Operator
- CDEC
- Coordinates
- 37.520°N, 120.309°W
- Last updated
- August 2, 2026
Recent readings
| Date | Fill level | Volume (hm³) |
|---|---|---|
| 2 Aug 2026 | 105.0% | 11 |
| 1 Aug 2026 | 102.4% | 10 |
| 30 Jul 2026 | 104.9% | 11 |
| 29 Jul 2026 | 95.4% | 10 |
| 28 Jul 2026 | 96.0% | 10 |
| 27 Jul 2026 | 102.2% | 10 |
| 26 Jul 2026 | 105.0% | 11 |
| 25 Jul 2026 | 105.0% | 11 |
| 24 Jul 2026 | 105.0% | 11 |
| 23 Jul 2026 | 104.0% | 11 |
| 22 Jul 2026 | 102.4% | 10 |
| 21 Jul 2026 | 105.0% | 11 |
Frequently asked questions
What is the current water level of Lake McSwain?
As of August 2, 2026, Lake McSwain is at 105.0% of its capacity, holding approximately 11 hm³ of water, according to CDEC (CA DWR) data.
Is Lake McSwain reservoir full?
Lake McSwain is essentially full, sitting at 105.0% of capacity as of August 2, 2026.
Is the water level at Lake McSwain rising or falling?
The level at Lake McSwain has been broadly stable over the latest week on record (0.0 points).
How much water can Lake McSwain hold?
Lake McSwain has a total capacity of 10 hm³.
Where is Lake McSwain reservoir located?
Lake McSwain is located in California, United States, within the California basin (coordinates 37.520°N, 120.309°W).
What is Lake McSwain used for?
Lake McSwain is used primarily for multiple purposes, and is managed by CDEC.