PROMISSÃO
São Paulo · TIETE
Capacity
7,408 hm³
Coordinates
-21.297°N, 49.783°W
Operator
ONS
95.5% full
Current fill
95.5%vs 7 days ago
-3.1%losing
vs 1 year ago
N/A7-day trend
↓falling
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 September 9, 2026, PROMISSÃO is filled to 95.5% of its total capacity, holding roughly 2,032 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 fallen by 3.1 percentage points.
Across the readings we hold for PROMISSÃO — 52 data points between September 26, 2025 and September 9, 2026 — the level has ranged from a low of 40.6% (October 31, 2025) to a high of 99.5% (August 14, 2026). On average the reservoir is fullest around August 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
- 95.5%
- Water stored
- 2,032 hm³
- Total capacity
- 7,408 hm³
- Usable capacity
- 2,127 hm³
- 7-day change
- ▼ 3.1 pts
- Primary use
- Hydroelectric power
- River
- TIETÊ
- River basin
- TIETE
- Operator
- ONS
- Coordinates
- 21.297°S, 49.783°W
- Last updated
- September 9, 2026
Recent readings
| Date | Fill level | Volume (hm³) |
|---|---|---|
| 9 Sep 2026 | 95.5% | 2,032 |
| 4 Sep 2026 | 98.6% | 2,098 |
| 28 Aug 2026 | 98.3% | 2,090 |
| 21 Aug 2026 | 97.5% | 2,074 |
| 14 Aug 2026 | 99.5% | 2,117 |
| 7 Aug 2026 | 98.5% | 2,096 |
| 31 Jul 2026 | 97.0% | 2,064 |
| 24 Jul 2026 | 99.0% | 2,106 |
| 17 Jul 2026 | 96.8% | 2,059 |
| 10 Jul 2026 | 94.8% | 2,017 |
| 3 Jul 2026 | 94.5% | 2,011 |
| 26 Jun 2026 | 98.3% | 2,090 |