Bravura Dam in the western Algarve
Bravura Dam in the western Algarve Photo: LUÍS FORRA/LUSA

Low level of Algarve water tables could increase salinity of water

Another peril of the drought

Groundwater tables in the Algarve have levels below what would be expected for this time of year, causing loss of quality in underground water and increasing the risk of salinisation (making freshwater ‘salty’) , the regional director of agriculture warned on Monday.

Speaking to Lusa, Pedro Valadas Monteiro, the Algarve regional director for DRAP (agriculture and fisheries), said that despite some groundwater tables showing levels below 25%, “no dramatic situations have yet been reported.

“There are one or two signs of some loss of quality (due to low levels of underground water reserves), but we still don’t have situations of cases where boreholes have dried up or of brackish or salty water. We haven’t reached that point yet,” he said – suggesting more that authorities are not yet aware of any of these situations.

The risk of saline intrusion in groundwater reserves is greater in aquifers located in coastal areas due to phenomena related to climate change, such as rising sea levels, greater frequency of droughts and lack of rainfall.

For Pedro Valadas Monteiro, the hot weather, low water levels in dams,  a reduction of groundwater flows and the likelihood of no rain for the next few months “leaves several uncertainties for the future of agriculture in the Algarve”.

“Despite agriculture in the Algarve using efficient irrigation systems, technology for monitoring water, techniques and recommendations that the regional directorate has encouraged, the cornerstone is the use of water in a very careful way,” he stressed.

Valadas Monteiro recalled that April was one of the hottest months since 1931, with the Algarve registering heat waves with temperatures above 30 degrees, registering a decrease of about 7% in water reserves in dams.

“Given this reality, we should all use water carefully – not only in the agricultural sector, but all economic sectors of the Algarve and in domestic consumption,” he said, referring that ‘management measures, some of which foresee the non-supply of water for two days a week, in order to try to preserve as much as possible and ensure that water availability can be extended for as long as possible. We don’t know what tomorrow will be like…”

According to Valadas Monteiro, the regional directorate “is attentive and concerned to maintain the conditions of viability to what is installed on the ground” (meaning agricultural explorations already in evidence).

“We have to adapt our practices and the use we make of the land to this scenario of less water, but with the concern to maintain what is already installed,” he repeated.

Regarding investments planned within the national water efficiency plan and in the Recovery and Resilience Plan (PRR), Valadas Monteiro warned that the availability of water “may not increase significantly in relation to what exists today.

“The most that will be achieved is not to have less water than there has been, but to have the same amount that we have been used to in the past, which requires careful management,” he stressed.

Portugal is currently experiencing a serious drought, with the Alentejo and Algarve regions in the most critical situation.