Experts drew attention to the costs and damages that may occur after the desalination method will be used to make seawater drinkable given the looming drought threats triggered by climate change.

Scientific and Technological Research Council of Türkiye (TÜBITAK) Marmara Research Center (MAM) Polar Research Institute General Director professor Burcu Özsoy regarding the changes they observed in Antarctica, said: "We see that terrestrial glaciers have severely separated from the mainland and integrated into the ocean. However, terrestrial ice also poses a great risk as it has the potential to increase sea levels."

Sea levels can rise by two different mechanisms due to climate change. First, as the oceans warm because of an increasing global temperature, seawater expands taking up more space in the ocean basin and causing a rise in water level. The second mechanism is the melting of ice over land, which then adds water to the ocean.

The drying up of lakes and other sources of fresh water in Türkiye has raised concerns as the country has started receiving alarms for a severe drought while planning for desalination of seawater is under consideration but will it be a safe and healthy solution? Let's read what our experts have to say to understand better.

Normally, there are two main ways to convert seawater into drinkable water: Reverse osmosis or flash desalination. Both require a lot of energy and the acquisition of technical science. It’s certainly a brilliant way to produce fresh water. However, it’s not without concerns from environmentalists who argue that the process is not only expensive but causes great damage to marine life that is the base layer of the marine food chain by desalination plants. And for each gallon of fresh water, a gallon or more of saline-salty water is returned to the sea.

Meanwhile, Middle East Technical University (METU) Marine Sciences Institute Director professor Barış Salihoğlu explained that freshwater resources are gradually decreasing because of the increasing population and climate change. He noted that there are several stages of seawater purification, which is a method used by many countries in the Mediterranean and Middle East basins to meet their water needs.

"First you get the water from the sea, then you have to pretreat it. There may be pollutants, living things and lime in it. After that, the desalination process is started followed by a disinfection method to turn it into drinking water which is pretty costly."

Pointing out that it is important to choose the point from which the water is collected to conduct the process, Salihoğlu mentioned that, "where the intense salty water that comes out after treatment will be discharged is a matter of discussion as well." Noting that the salinity of wastewater can be up to twice the natural salinity, Salihoğlu continued: "Our model studies have shown that water collected from slightly mid-sea does less damage than deep-sea habitats."

Underscoring that according to the new regulations, such facilities should work with renewable energy against carbon emissions, Salihoğlu emphasized that the first condition is to turn to solar and wind energy in the facilities.

Expressing concern that Türkiye is a country that needs to be very careful about its water resources, and that water conservation can be implemented through regulating policies, Salihoğlu expressed that seawater purification can be applied at the regional level.

Dokuz Eylul University Engineering Faculty Environmental Engineering Department Environmental Technologies Department lecturer professor Azize Ayol noted that especially with the development of membrane technologies, reverse osmosis systems have come to the fore in the desalination of seawater.

"The methods of desalination of seawater and treatment of drinking water from seawater have evolved from evaporation technologies to membrane technologies. With this method, you can completely desalinate water," Ayol explained.

Ayol added, "such facilities have been operating in many countries of the world for a long time and are used in Israel, Saudi Arabia, Spain, Canary Islands, the U.S. and Australia, reminding that there is a facility that purifies seawater on Avşa Island in Türkiye."

"If you are a country struggling with water scarcity and investment costs, install this system because you don't have water. The cost varies according to the region and energy needs. The larger the facility capacity, the lower the initial investment costs. The quality of the seawater you receive is also important. Different pretreatments are applied for these facilities. These are the processes that affect the initial investment costs. Membrane technology is developing quickly. As this improves, the cost will improve too."

Touching upon the operating cost apart from the investment, Ayol noted that, "the operating cost for 1 cubic meter of clean water varies between 30 to 90 cents. We need to purify and process this water separately. In developing technologies, it is possible to obtain energy by utilizing the hydrostatic pressure in the concentrated stream and use it in the facility's operation because the cost decreases when energy-efficient facilities are established," she explained.

Saying that Türkiye is experiencing "water scarcity," Ayol said that the country's need for drinking water is 7-8 billion cubic meters per year, and although this need can be met with existing resources, there are occasional problems in coastal areas, especially in summer, and that seawater is not available in such places, indicating that the purification method could be applied in such situations."

Regarding the widespread use of seawater treatment technology in Türkiye, Ayol said: "It is not a critical need, it is important for us to use conventional water resources, to prevent loss and leakage and to use water resources more economically and efficiently," she emphasized.