Andalucía's reservoirs keep falling, but water reserves remain strong

Water levels have declined for five months, yet reservoirs are still holding almost twice their ten-year average

Andalucía’s reservoirs have been losing water for more than five consecutive months, but reserves remain comfortably above the long-term average following the heavy rainfall earlier this year.

Figures published by Spain’s Ministry for Ecological Transition and the Demographic Challenge (Miteco) show that reservoirs across the region held 7,614 cubic hectometres of water on Tuesday October 20, equivalent to 68.69% of their total capacity.

That is a significant drop from May, when levels reached 86.7% after almost six months of continuous gains. The first decline was recorded on May 19 and reserves have continued to fall since then.

The longer-term comparison, however, puts the latest figures into perspective. Current reserves are 2,956 hm³ higher than during the same week in 2025 and stand almost 34 percentage points above the average for the past decade. That ten-year average is 34.86%, equivalent to 3,864 hm³.

The figures mark a change from February, when persistent rainfall was causing disruption to farms while helping replenish the region’s reservoirs. The heavy rain brought mixed fortunes for Andalucía, with agricultural work disrupted as water reserves surged.

The latest figures show that water levels have eased across several of the region’s main river basins, although reserves remain substantially higher than a year ago.

The Guadalquivir basin, home to Andalucía’s largest reservoirs, is at 68.5% capacity, holding 5,504 hm³. That is 17 hm³ less than a week earlier, but 2,194 hm³ more than the 3,310 hm³ recorded at the same point last year.

In the Andalusian Mediterranean basin, reserves have slipped to 62.9%, with 739 hm³ of water. This is four hm³ down on the previous week, but remains above both the ten-year average of 440 hm³ and last year’s figure of 518 hm³.

In Huelva, reservoirs serving the Tinto, Odiel and Piedras rivers remain unchanged at 140 hm³, or 61.1% capacity. That is slightly below the ten-year average of 148 hm³ and five hm³ less than a year ago.

In Cádiz, the Guadalete-Barbate reservoir area has fallen to 74.6% capacity, holding 1,231 hm³. Despite the recent decline, this is 546 hm³ more than at the same time last year.

Across Spain, reservoirs are 57.2% full, holding 32,062 hm³ after a weekly fall of 352 hm³. Andalucía’s reserves therefore remain well above the national level, even after months of gradual losses.

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