SANTO ANTONIO
Rondônia · AMAZONAS
Capacity
2,282.8 hm³
Coordinates
-8.801°N, 63.950°W
Operator
ONS
51.9% full
Current fill
51.9%vs 7 days ago
0.0%stable
vs 1 year ago
-46.5%year-over-year
7-day trend
→stable
Catchment Weather
Past 30 days + 14-day forecast · Open-Meteo
Technical specifications
| Total capacity | 2,282.8 hm³ |
| Usable capacity | 489.87 hm³ |
| Primary use | Hydroelectric |
| Operator | ONS |
| River | MADEIRA |
| Province | Rondônia |
| River basin | AMAZONAS |
Satellite imagery: Esri, Maxar, Earthstar Geographics. Map: Esri, HERE, Garmin, © OpenStreetMap contributors. -8.801, -63.950 · Open in Google Maps
About SANTO ANTONIO
As of July 28, 2026, SANTO ANTONIO is filled to 51.9% of its total capacity, holding roughly 254 hm³ of water out of a maximum 2,283 hm³. At this level the reservoir is within its normal operating range. Of that total, about 490 hm³ is usable (live) storage.
Over the most recent week on record the fill level has held broadly steady (+0.0 pts), and it is 46.5 points below its level on the same date a year earlier.
Across the readings we hold for SANTO ANTONIO — 52 data points between August 15, 2025 and July 28, 2026 — the level has ranged from a low of 35.9% (October 10, 2025) to a high of 100.0% (November 28, 2025). On average the reservoir is fullest around April and at its lowest around October.
It is operated by ONS primarily for hydroelectric power. It lies within the AMAZONAS basin at 8.801°S, 63.950°W.
Key facts
- Current fill level
- 51.9%
- Water stored
- 254 hm³
- Total capacity
- 2,283 hm³
- Usable capacity
- 490 hm³
- 7-day change
- No change
- Year-on-year
- ▼ 46.5 pts
- Primary use
- Hydroelectric power
- River
- MADEIRA
- River basin
- AMAZONAS
- Operator
- ONS
- Coordinates
- 8.801°S, 63.950°W
- Last updated
- July 28, 2026
Recent readings
| Date | Fill level | Volume (hm³) |
|---|---|---|
| 28 Jul 2026 | 51.9% | 254 |
| 24 Jul 2026 | 51.9% | 254 |
| 17 Jul 2026 | 80.8% | 396 |
| 10 Jul 2026 | 99.2% | 486 |
| 3 Jul 2026 | 98.4% | 482 |
| 26 Jun 2026 | 98.4% | 482 |
| 19 Jun 2026 | 98.4% | 482 |
| 12 Jun 2026 | 98.4% | 482 |
| 5 Jun 2026 | 98.4% | 482 |
| 29 May 2026 | 98.4% | 482 |
| 22 May 2026 | 99.2% | 486 |
| 15 May 2026 | 98.4% | 482 |
Frequently asked questions
What is the current water level of SANTO ANTONIO?
As of July 28, 2026, SANTO ANTONIO is at 51.9% of its capacity, holding approximately 254 hm³ of water, according to ONS – Operador Nacional do Sistema Elétrico data.
Is SANTO ANTONIO reservoir full?
No. As of July 28, 2026, SANTO ANTONIO is within its normal operating range at 51.9% of its capacity, so it is not full.
Is the water level at SANTO ANTONIO rising or falling?
The level at SANTO ANTONIO has been broadly stable over the latest week on record (0.0 points).
How much water can SANTO ANTONIO hold?
SANTO ANTONIO has a total capacity of 2,283 hm³, of which about 490 hm³ is usable storage.
Where is SANTO ANTONIO reservoir located?
SANTO ANTONIO is located in Rondônia, Brazil, within the AMAZONAS basin (coordinates 8.801°S, 63.950°W).
What is SANTO ANTONIO used for?
SANTO ANTONIO is used primarily for hydroelectric power, and is managed by ONS.