P. AFONSO 4
Bahia · SAO FRANCISCO
Capacity
1,277 hm³
Coordinates
-9.416°N, 38.211°W
Operator
ONS
67.5% full
Current fill
67.5%vs 7 days ago
+12.4%gaining
vs 1 year ago
-5.3%year-over-year
7-day trend
↑rising
Catchment Weather
Past 30 days + 14-day forecast · Open-Meteo
Technical specifications
| Total capacity | 1,277 hm³ |
| Usable capacity | 209 hm³ |
| Primary use | Hydroelectric |
| Operator | ONS |
| River | SÃO FRANCISCO |
| Province | Bahia |
| River basin | SAO FRANCISCO |
Satellite imagery: Esri, Maxar, Earthstar Geographics. Map: Esri, HERE, Garmin, © OpenStreetMap contributors. -9.416, -38.211 · Open in Google Maps
About P. AFONSO 4
As of July 28, 2026, P. AFONSO 4 is filled to 67.5% of its total capacity, holding roughly 141 hm³ of water out of a maximum 1,277 hm³. At this level the reservoir is within its normal operating range. Of that total, about 209 hm³ is usable (live) storage.
Over the most recent week on record the fill level has risen by 12.4 percentage points, and it is 5.3 points below its level on the same date a year earlier.
Across the readings we hold for P. AFONSO 4 — 52 data points between August 15, 2025 and July 28, 2026 — the level has ranged from a low of 55.0% (July 24, 2026) to a high of 75.6% (December 19, 2025). On average the reservoir is fullest around February and at its lowest around July.
It is operated by ONS primarily for hydroelectric power. It lies within the SAO FRANCISCO basin at 9.416°S, 38.211°W.
Key facts
- Current fill level
- 67.5%
- Water stored
- 141 hm³
- Total capacity
- 1,277 hm³
- Usable capacity
- 209 hm³
- 7-day change
- ▲ 12.4 pts
- Year-on-year
- ▼ 5.3 pts
- Primary use
- Hydroelectric power
- River
- SÃO FRANCISCO
- River basin
- SAO FRANCISCO
- Operator
- ONS
- Coordinates
- 9.416°S, 38.211°W
- Last updated
- July 28, 2026
Recent readings
| Date | Fill level | Volume (hm³) |
|---|---|---|
| 28 Jul 2026 | 67.5% | 141 |
| 24 Jul 2026 | 55.0% | 115 |
| 17 Jul 2026 | 67.5% | 141 |
| 10 Jul 2026 | 57.9% | 121 |
| 3 Jul 2026 | 61.7% | 129 |
| 26 Jun 2026 | 65.5% | 137 |
| 19 Jun 2026 | 63.6% | 133 |
| 12 Jun 2026 | 58.4% | 122 |
| 5 Jun 2026 | 67.9% | 142 |
| 29 May 2026 | 64.1% | 134 |
| 22 May 2026 | 65.5% | 137 |
| 15 May 2026 | 66.0% | 138 |
Frequently asked questions
What is the current water level of P. AFONSO 4?
As of July 28, 2026, P. AFONSO 4 is at 67.5% of its capacity, holding approximately 141 hm³ of water, according to ONS – Operador Nacional do Sistema Elétrico data.
Is P. AFONSO 4 reservoir full?
No. As of July 28, 2026, P. AFONSO 4 is within its normal operating range at 67.5% of its capacity, so it is not full.
Is the water level at P. AFONSO 4 rising or falling?
The level at P. AFONSO 4 is rising — it gained 12.4 percentage points over the latest week on record.
How much water can P. AFONSO 4 hold?
P. AFONSO 4 has a total capacity of 1,277 hm³, of which about 209 hm³ is usable storage.
Where is P. AFONSO 4 reservoir located?
P. AFONSO 4 is located in Bahia, Brazil, within the SAO FRANCISCO basin (coordinates 9.416°S, 38.211°W).
What is P. AFONSO 4 used for?
P. AFONSO 4 is used primarily for hydroelectric power, and is managed by ONS.