Water: where Spain's droughts hit hardest
Droughts and water restrictions are part of the climate story. Which places depend on reservoirs that ran dry?
Spain's recent droughts were real: in 2023 and 2024 parts of Catalonia and Andalusia had water restrictions. How exposed is each place? We looked at the reservoirs of the river basin each town depends on, week by week from 2016 to 2025.
Lowest weekly reservoir level, 2016-2025, by river basin (% full)
The Segura basin fell to 13% (2017-11) and was below 40% full in 83% of all weeks. At the other end the Eastern Cantabrian basin never went below 59%. The northern basins (Galicia, Asturias, Cantabria, the Basque Country) stayed above a third full even in the worst weeks.
| River basin | Lowest week | Weeks below 40% | Now (2026-09-29) | Same week, 10-year average | Places |
|---|---|---|---|---|---|
| Segura | 13% (2017-11) | 83% | 50% | 26% | 19 |
| Guadalete-Barbate | 14% (2024-01) | 45% | 76% | 38% | 8 |
| Catalan internal basins | 14% (2024-03) | 26% | 74% | 58% | 53 |
| Guadalquivir | 18% (2023-10) | 49% | 70% | 34% | 25 |
| Andalusian Mediterranean basins | 18% (2024-02) | 39% | 64% | 39% | 26 |
| Guadiana | 23% (2022-12) | 38% | 72% | 40% | 10 |
| Júcar | 25% (2017-12) | 37% | 52% | 40% | 52 |
| Duero | 29% (2017-12) | 10% | 51% | 49% | 11 |
| Ebro | 33% (2023-10) | 5% | 46% | 51% | 10 |
| Tajo | 34% (2019-10) | 9% | 55% | 47% | 41 |
| Miño-Sil | 37% (2017-12) | 1% | 58% | 56% | 3 |
| Galician coast | 38% (2017-12) | 0% | 52% | 56% | 15 |
| Tinto, Odiel and Piedras | 51% (2023-10) | 0% | 65% | 67% | 2 |
| Western Cantabrian | 51% (2017-12) | 0% | 59% | 66% | 11 |
| Eastern Cantabrian | 59% (2016-11) | 0% | 60% | 72% | 13 |
Not the whole story
Reservoirs are not the only source. The Segura basin (Murcia and southern Alicante) also receives water through a transfer from the Tagus and from desalination plants, so its low reservoir figures overstate the risk of taps running dry. The 34 places on the Balearic and Canary Islands, in Ceuta and in Melilla are not covered: they rely mainly on groundwater and desalination.
How we did this
Ministry for the Ecological Transition, Boletín Hidrológico database (weekly, reservoirs over 5 hm³, 1988-2026), summed per river basin; each place assigned to its basin with the ministry's official boundaries. Built 2026-10-18.