TRÊS IRMÃOS
São Paulo · TIETE
Capacity
13,372 hm³
Coordinates
-20.669°N, 51.297°W
Operator
ONS
Current fill
63.8%vs 7 days ago
+1.0%gaining
vs 1 year ago
-8.5%year-over-year
7-day trend
→stable
Catchment Weather
Past 30 days + 14-day forecast · Open-Meteo
Technical specifications
| Total capacity | 13,372 hm³ |
| Usable capacity | 3,447.98 hm³ |
| Primary use | Hydroelectric |
| Operator | ONS |
| River | TIETÊ |
| Province | São Paulo |
| River basin | TIETE |
Satellite imagery: Esri, Maxar, Earthstar Geographics. Map: Esri, HERE, Garmin, © OpenStreetMap contributors. -20.669, -51.297 · Open in Google Maps
About TRÊS IRMÃOS
As of June 10, 2026, TRÊS IRMÃOS is filled to 63.8% of its total capacity, holding roughly 2,200 hm³ of water out of a maximum 13,372 hm³. At this level the reservoir is within its normal operating range. Of that total, about 3,448 hm³ is usable (live) storage.
Over the most recent week on record the fill level has held broadly steady (+1.0 pts), and it is 8.5 points below its level on the same date a year earlier.
Across the readings we hold for TRÊS IRMÃOS — 52 data points between June 27, 2025 and June 10, 2026 — the level has ranged from a low of 56.4% (November 28, 2025) to a high of 92.8% (March 27, 2026). On average the reservoir is fullest around March and at its lowest around November.
It is operated by ONS primarily for hydroelectric power. It lies within the TIETE basin at 20.669°S, 51.297°W.
Key facts
- Current fill level
- 63.8%
- Water stored
- 2,200 hm³
- Total capacity
- 13,372 hm³
- Usable capacity
- 3,448 hm³
- 7-day change
- ▲ 1.0 pts
- Year-on-year
- ▼ 8.5 pts
- Primary use
- Hydroelectric power
- River
- TIETÊ
- River basin
- TIETE
- Operator
- ONS
- Coordinates
- 20.669°S, 51.297°W
- Last updated
- June 10, 2026
Recent readings
| Date | Fill level | Volume (hm³) |
|---|---|---|
| 10 Jun 2026 | 63.8% | 2,200 |
| 5 Jun 2026 | 62.8% | 2,165 |
| 29 May 2026 | 61.8% | 2,129 |
| 22 May 2026 | 60.3% | 2,080 |
| 15 May 2026 | 57.0% | 1,967 |
| 8 May 2026 | 63.2% | 2,179 |
| 1 May 2026 | 69.6% | 2,401 |
| 24 Apr 2026 | 78.4% | 2,705 |
| 17 Apr 2026 | 86.5% | 2,984 |
| 10 Apr 2026 | 91.7% | 3,163 |
| 3 Apr 2026 | 91.7% | 3,163 |
| 27 Mar 2026 | 92.8% | 3,200 |
Frequently asked questions
What is the current water level of TRÊS IRMÃOS?
As of June 10, 2026, TRÊS IRMÃOS is at 63.8% of its capacity, holding approximately 2,200 hm³ of water, according to ONS – Operador Nacional do Sistema Elétrico data.
Is TRÊS IRMÃOS reservoir full?
No. As of June 10, 2026, TRÊS IRMÃOS is within its normal operating range at 63.8% of its capacity, so it is not full.
Is the water level at TRÊS IRMÃOS rising or falling?
The level at TRÊS IRMÃOS has been broadly stable over the latest week on record (+1.0 points).
How much water can TRÊS IRMÃOS hold?
TRÊS IRMÃOS has a total capacity of 13,372 hm³, of which about 3,448 hm³ is usable storage.
Where is TRÊS IRMÃOS reservoir located?
TRÊS IRMÃOS is located in São Paulo, Brazil, within the TIETE basin (coordinates 20.669°S, 51.297°W).
What is TRÊS IRMÃOS used for?
TRÊS IRMÃOS is used primarily for hydroelectric power, and is managed by ONS.