RONDON II
Rondônia · AMAZONAS
Capacity
478.29 hm³
Coordinates
-11.997°N, 60.697°W
Operator
ONS
69.3% full
Current fill
69.3%vs 7 days ago
-4.2%losing
vs 1 year ago
-4.2%year-over-year
7-day trend
↓falling
Catchment Weather
Past 30 days + 14-day forecast · Open-Meteo
Technical specifications
| Total capacity | 478.29 hm³ |
| Usable capacity | 286.12 hm³ |
| Primary use | Hydroelectric |
| Operator | ONS |
| River | JI-PARANA |
| Province | Rondônia |
| River basin | AMAZONAS |
Satellite imagery: Esri, Maxar, Earthstar Geographics. Map: Esri, HERE, Garmin, © OpenStreetMap contributors. -11.997, -60.697 · Open in Google Maps
About RONDON II
As of July 28, 2026, RONDON II is filled to 69.3% of its total capacity, holding roughly 198 hm³ of water out of a maximum 478 hm³. At this level the reservoir is within its normal operating range. Of that total, about 286 hm³ is usable (live) storage.
Over the most recent week on record the fill level has fallen by 4.2 percentage points, and it is 4.2 points below its level on the same date a year earlier.
Across the readings we hold for RONDON II — 52 data points between August 15, 2025 and July 28, 2026 — the level has ranged from a low of 15.2% (November 28, 2025) to a high of 105.0% (April 24, 2026). On average the reservoir is fullest around April and at its lowest around November.
It is operated by ONS primarily for hydroelectric power. It lies within the AMAZONAS basin at 11.997°S, 60.697°W.
Key facts
- Current fill level
- 69.3%
- Water stored
- 198 hm³
- Total capacity
- 478 hm³
- Usable capacity
- 286 hm³
- 7-day change
- ▼ 4.2 pts
- Year-on-year
- ▼ 4.2 pts
- Primary use
- Hydroelectric power
- River
- JI-PARANA
- River basin
- AMAZONAS
- Operator
- ONS
- Coordinates
- 11.997°S, 60.697°W
- Last updated
- July 28, 2026
Recent readings
| Date | Fill level | Volume (hm³) |
|---|---|---|
| 28 Jul 2026 | 69.3% | 198 |
| 24 Jul 2026 | 73.5% | 210 |
| 17 Jul 2026 | 78.3% | 224 |
| 10 Jul 2026 | 80.7% | 231 |
| 3 Jul 2026 | 83.4% | 239 |
| 26 Jun 2026 | 86.4% | 247 |
| 19 Jun 2026 | 90.4% | 259 |
| 12 Jun 2026 | 91.6% | 262 |
| 5 Jun 2026 | 93.6% | 268 |
| 29 May 2026 | 94.3% | 270 |
| 22 May 2026 | 95.8% | 274 |
| 15 May 2026 | 94.3% | 270 |
Frequently asked questions
What is the current water level of RONDON II?
As of July 28, 2026, RONDON II is at 69.3% of its capacity, holding approximately 198 hm³ of water, according to ONS – Operador Nacional do Sistema Elétrico data.
Is RONDON II reservoir full?
No. As of July 28, 2026, RONDON II is within its normal operating range at 69.3% of its capacity, so it is not full.
Is the water level at RONDON II rising or falling?
The level at RONDON II is falling — it dropped 4.2 percentage points over the latest week on record.
How much water can RONDON II hold?
RONDON II has a total capacity of 478 hm³, of which about 286 hm³ is usable storage.
Where is RONDON II reservoir located?
RONDON II is located in Rondônia, Brazil, within the AMAZONAS basin (coordinates 11.997°S, 60.697°W).
What is RONDON II used for?
RONDON II is used primarily for hydroelectric power, and is managed by ONS.