As the Algarve studies ways to adapt to the devastating reality of drought, desalination is being discussed as one of the main solutions to ensure water supply.
Vila Vita Parc resort in Porches is already considered a success story for using transformed seawater to supply its pools and water its gardens.
The resort implemented its desalination system in 2015, with the plan initially being to only use the treated seawater for irrigation. However, the project quickly expanded.
“We realised that the amount of water from our desalination system would allow us to supply our lakes as well. Now, we are also using it to supply seven pools,” André Menitra Matos, Vila Vita Parc’s Quality and Environment Director, told Lusa news agency.
The resort’s desalination station is located underground beneath a tennis court and is imperceptible to guests. It supplies around 70% of Vila Vita Parc’s water needs.
Only around 30% of the resort’s water comes from the water distribution system to supply the rooms, bathrooms and restaurants.
Happy about the amount of water that the resort has been able to save, Matos says that, as “responsible polluters”, it is important for Vila Vita Parc and other similar businesses to respect the environment through sustainable solutions.
Vila Vita Parc’s desalination system is able to collect around 24,000 litres of water per hour and around 444,000 litres per day, which, in other words, represent “around 900 pools of 650m3” at the end of the year.
Another success story is that of restaurant owner José Vargas who installed a much smaller desalination system underneath his establishment on Faro’s Ilha Deserta around 12 years ago.
Like the system at Vila Vita Parc, it uses a purification process known as reverse osmosis that forces the seawater through a membrane that removes the salt, turning it into potable water.
“We had to resort to this solution because there wasn’t any other. As we don’t have a water supply network or any freshwater boreholes, we had to resort to desalination,” said Vargas.
Desalination is also one of the proposals included in a plan that is being drawn up for Culatra Island, another of the Ria Formosa barrier islands which has its own school, social centre, health centre and church.
“It is a crucial project for the island in terms of safe drinking water. However, it is also probably the most expensive solution,” explained André Pacheco, coordinator of the Culatra 2030 – Comunidade Energética Sustentável (Sustainable Energy Community) project.
The island has been linked to Faro’s public water network since 2009, although Pacheco admits that “a lot of energy is used pumping potable water to the island and pumping wastewater back to the mainland’s treatment plants”.
One of the concerns surrounding the desalination project, he said, was to do with the wastewater that will be produced. In fact, Pacheco admitted that there is still a lot of research that needs to be carried out before the project moves forward.
But as he pointed out, the solution to the island’s water needs won’t rely solely on desalination – “water has to start being looked at differently”.
“We use potable water for many things that we don’t need to: we wash our cars with this water!”
Desalination won’t solve all problems
While acknowledging that it is a viable solution, a researcher from the University of the Algarve’s Centre of Marine and Environmental Research (CIMA) has warned that desalination shouldn’t be the “only answer” to the drought issues.
“I believe it is an option, but it needs to be integrated with others,” Manuela Moreira da Silva told Lusa news agency.
She highlighted some of the “difficulties caused by desalination”, such as deciding what to do with the wastewater that is generated by the chemical procedure to remove salt from seawater.
The researcher warned that around half of the seawater that is treated has no use and is left with a high amount of chemicals – “this “environmental impact should be considered.”
Still, she says that the process is one of the solutions that should be studied and praised the project that is underway in Culatra, adding that desalination could be “a very interesting complementary solution”.
Moreira da Silva’s statement came after Portugal’s environment minister said that building more dams wouldn’t solve the Algarve’s water issues and that the solution lies in more efficient water management as well as the construction of a desalination plant.
While she partly agrees with the minister’s statement, she says that the “best solution today” may not be so in the near future, giving the example of the Foupana dam which she believes “should have been built 20 years ago”.
“Today, I have many doubts about it, as the reality has completely changed,” she said.
Instead of new dams, she suggested another solution which would involve building reservoirs in towns which are particularly affected by climate change, so that they can collect rainwater and channel it to areas in need.
“All solutions should be studied to save energy and water and contribute to carbon neutrality,” the researcher said, saying that this is a “great challenge” that will need “much more than just the construction of dams”.
Algarve mayors learn from Spanish example
Last month, nine mayors from the Algarve travelled to Spain to learn more about desalination systems implemented in that country.
Their trip included stops at the Denia technological centre, two desalination plants in Racons and La Marina Baja in Alicante and two wastewater treatment plants in La Gavia and Ávila.
“At a time when measures to tackle the effects of climate change are being debated and implemented, we need to put all solutions ‘on the table’ so that we can weigh the pros and cons, costs and environmental impact of every alternative to the production of drinking water,” said Vila Real de Santo António Mayor Conceição Cabrita.
The mayors of Olhão, Loulé, Faro, Albufeira, Lagoa, Alcoutim, Castro Marim and Monchique also embarked on the trip.
By MICHAEL BRUXO