Malaga province's reservoirs set for their best record in last ten years

Following the abundant rains in December and January, Malaga province's dam network is set to achieve its best record of the past decade. On 26 January, right before another rainy forecast, surface reserves amounted to 367 million cubic metres, which is more than 60 per cent of their capacity.

The forecast for this week promises more rainfall and subsequent runoffs, guaranteeing the milestone.

In the last month, the province's reservoirs have gained 90 million cubic metres, which is the equivalent of the yearly demand of the entire Costa del Sol. It is also twice the annual demand of Malaga city. There is enough water for two or three years of peace, which could be disrupted by climatic and demographic changes.

Water gains occur in spite of the latest reservoir releases. The La Concepción dam between Marbella and Istán, for example, is not allowed to exceed 48 million cubic metres in winter. For this reason, its floodgates have already opened on two occasions to release more than five million cubic metres and prevent flooding. Another release is possibly going to take place in the next few days.

The Casasola dam in Almogía also released water a few days ago, although for a different reason. The dam is at risk of blockages caused by the dragging of sediments in the bottom drains. Experts have estimated that, after last year's heavy rains, a third of the reservoir was clogged.

Similar is the fate of Tajo de la Encantada, to which the three Guadalhorce reservoirs are connected. On Monday, spokespersons for the municipalities in the area announced that release work would be carried out from 10am on 26 January to 10am on Tuesday.

"The current flow of the Guadalhorce river will be increased by opening the sluice gates of the Tajo de la Encantada dam, which will release 15 cubic metres per second," they warned.

The previous decade closed with an outstanding hydrological year in 2020, when reservoir levels reached 414 million cubic metres at the start of spring. This was followed by the recent and prolonged drought, which did not ease until last year, when reservoirs rose to 377 million cubic metres.

Now levels are just ten million cubic metres short of that, with the entire rainy season still ahead. Current runoff alone is almost enough to reach that mark.

Looking back a year gives a good perspective on how the situation has taken a 180-degree turn. The reservoir that stores the most water, the Guadalteba, is now approaching 100 million cubic metres. Last year it only had 32.

Second is La Viñuela, which exceeds 80 million cubic metres, compared to 36 a year ago.

Both the Conde de Guadalhorce and the Guadalhorce dams, whose water reserves are affected by salinity from the Meliones spring, accumulate 58 million cubic metres. They have, respectively, doubled and almost tripled their 2025 reserves.

Next comes the La Concepción reservoir, which would have reached its capacity of 57 million cubic metres, had it not been for the releases. The dam has proved to be too small for the generous inflows from the Verde river, the Guadaiza-Guadalmina-Guadalmansa system and the rainy areas of Serranía de Ronda and Sierra de las Nieves.

Expansion plans for the reservoir, however, are not on the table. This means that management will continue releasing water when needed.

The main role of the Casasola and Limonero dams is to prevent floods, but their water can be used if needed. They currently store some 12 million cubic metres each.

El Limonero's capacity was modified in order to ensure greater safety for the city of Malaga. Its safety level used to be set at 21 million cubic metres, but it dropped to 14 - a level that is only exceeded in the event of floods.

In terms of the drought crisis, the Costa del Sol has been in a normal situation for some time. There are no restrictions in terms of inflows to the headwater reservoirs.

Malaga city is also theoretically in a phase of normality, having overcome moderation as per what the drought committee decided a year ago. The city has an allowance of 225 litres per inhabitant per day, enough to ensure a stable water supply, even though this represents around 90% of the usual demand.

The outlook is also positive for agricultural irrigation this year. Farmers already received 30 million cubic metres of water last year and conditions suggest further improvements ahead.

La Viñuela can make the leap to a phase of moderate drought, but not to normality, for which it needs more than 90.5 million cubic metres. This suggests that the drought committee will restrict irrigation in the Axarquia district once again this year. The allowance, however, will probably be above the 12 million cubic metres set in 2025.