Alsa - Mediajo
Cantábrico Occidental
Capacity
22 hm³
Coordinates
43.084°N, 4.002°W
Operator
Cantábrico Occidental
86.4% full
Current fill
86.4%vs 13 Oct 2026
0.0 ppstable
vs 1 year ago
+9.1 ppyear-over-year
Trend
→stable
Drought context
Storage vs October average
145%of normal
86.4% full on 2026-10-19, against an average of 59.6% for October across 9 years of readings (+26.8 points).
Rain over the last three months · 11 October 2026
Near normal
In the three months to 11 October 2026 the area around Alsa - Mediajo had rain close to normal for the season. Rainfall compared with the long-run record for the same season at this point (Copernicus Global Drought Observatory, SPI-3 index −0.24). Rain, not storage.
EU drought indicator · 11 October 2026
Noneno drought signal
The European Drought Observatory's combined reading of rain, soil moisture and vegetation at this point. Watch means rain has been short, Warning that the soil has dried out, Alert that vegetation is visibly stressed; Recovery means the shortfall is easing. Ground conditions, not the reservoir's storage. Spain drought figures →
Catchment Weather
Past 30 days + 14-day forecast · Open-Meteo
Technical specifications
| Total capacity | 22 hm³ |
| Primary use | — |
| Operator | Cantábrico Occidental |
| River basin | Cantábrico Occidental |
Satellite imagery: Esri, Maxar, Earthstar Geographics. Map: Esri, HERE, Garmin, © OpenStreetMap contributors. 43.084°N, 4.002°W · Open in Google Maps
About Alsa - Mediajo
As of October 19, 2026, Alsa - Mediajo is filled to 86.4% of its total capacity, holding 19 hm³ of water out of a maximum 22 hm³. At this level the reservoir is high.
Since October 13, 2026 the fill level has held broadly steady (+0.0 pp), and it is 9.1 points above its level on the same date a year earlier.
Across the readings we hold for Alsa - Mediajo — 419 data points between October 16, 2018 and October 19, 2026 — the level has ranged from a low of 63.6% (November 8, 2022) to a high of 104.5% (March 31, 2026). On average the reservoir is fullest around May and at its lowest around November.
It is operated by Cantábrico Occidental. It lies within the Cantábrico Occidental basin at 43.084°N, 4.002°W.
Key facts
- Current fill level
- 86.4% of total capacity
- Water stored
- 19 hm³
- Total capacity
- 22 hm³
- Change since October 13, 2026
- No change
- Year-on-year
- ▲ 9.1 pp
- River basin
- Cantábrico Occidental
- Operator
- Cantábrico Occidental
- Coordinates
- 43.084°N, 4.002°W
- Last updated
- October 19, 2026
Recent readings
| Date | Fill level | Volume (hm³) |
|---|---|---|
| 19 Oct 2026 | 86.4% | 19 |
| 13 Oct 2026 | 86.4% | 19 |
| 6 Oct 2026 | 81.8% | 18 |
| 29 Sep 2026 | 86.4% | 19 |
| 22 Sep 2026 | 86.4% | 19 |
| 15 Sep 2026 | 86.4% | 19 |
| 8 Sep 2026 | 86.4% | 19 |
| 1 Sep 2026 | 86.4% | 19 |
| 25 Aug 2026 | 90.9% | 20 |
| 18 Aug 2026 | 86.4% | 19 |
| 11 Aug 2026 | 86.4% | 19 |
| 4 Aug 2026 | 90.9% | 20 |