PROMISSÃO
São Paulo · TIETE
Capacity
7,408 hm³
Coordinates
-21.297°N, 49.783°W
Operator
ONS
98.0% full
Current fill
98.0%vs 7 days ago
-1.0%losing
vs 1 year ago
+32.1%year-over-year
7-day trend
→stable
Catchment Weather
Past 30 days + 14-day forecast · Open-Meteo
Technical specifications
| Total capacity | 7,408 hm³ |
| Usable capacity | 2,127.3 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. -21.297, -49.783 · Open in Google Maps
About PROMISSÃO
As of July 28, 2026, PROMISSÃO is filled to 98.0% of its total capacity, holding roughly 2,085 hm³ of water out of a maximum 7,408 hm³. At this level the reservoir is high. Of that total, about 2,127 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 32.1 points above its level on the same date a year earlier.
Across the readings we hold for PROMISSÃO — 52 data points between August 15, 2025 and July 28, 2026 — the level has ranged from a low of 40.6% (October 31, 2025) to a high of 99.0% (July 24, 2026). On average the reservoir is fullest around May and at its lowest around October.
It is operated by ONS primarily for hydroelectric power. It lies within the TIETE basin at 21.297°S, 49.783°W.
Key facts
- Current fill level
- 98.0%
- Water stored
- 2,085 hm³
- Total capacity
- 7,408 hm³
- Usable capacity
- 2,127 hm³
- 7-day change
- ▼ 1.0 pts
- Year-on-year
- ▲ 32.1 pts
- Primary use
- Hydroelectric power
- River
- TIETÊ
- River basin
- TIETE
- Operator
- ONS
- Coordinates
- 21.297°S, 49.783°W
- Last updated
- July 28, 2026
Recent readings
| Date | Fill level | Volume (hm³) |
|---|---|---|
| 28 Jul 2026 | 98.0% | 2,085 |
| 24 Jul 2026 | 99.0% | 2,106 |
| 17 Jul 2026 | 96.5% | 2,053 |
| 10 Jul 2026 | 95.0% | 2,022 |
| 3 Jul 2026 | 94.5% | 2,011 |
| 26 Jun 2026 | 98.3% | 2,090 |
| 19 Jun 2026 | 96.8% | 2,059 |
| 12 Jun 2026 | 98.3% | 2,090 |
| 5 Jun 2026 | 97.8% | 2,080 |
| 29 May 2026 | 97.3% | 2,069 |
| 22 May 2026 | 98.3% | 2,090 |
| 15 May 2026 | 98.5% | 2,096 |
Frequently asked questions
What is the current water level of PROMISSÃO?
As of July 28, 2026, PROMISSÃO is at 98.0% of its capacity, holding approximately 2,085 hm³ of water, according to ONS – Operador Nacional do Sistema Elétrico data.
Is PROMISSÃO reservoir full?
PROMISSÃO is essentially full, sitting at 98.0% of capacity as of July 28, 2026.
Is the water level at PROMISSÃO rising or falling?
The level at PROMISSÃO has been broadly stable over the latest week on record (-1.0 points).
How much water can PROMISSÃO hold?
PROMISSÃO has a total capacity of 7,408 hm³, of which about 2,127 hm³ is usable storage.
Where is PROMISSÃO reservoir located?
PROMISSÃO is located in São Paulo, Brazil, within the TIETE basin (coordinates 21.297°S, 49.783°W).
What is PROMISSÃO used for?
PROMISSÃO is used primarily for hydroelectric power, and is managed by ONS.