The world’s thirst for fresh water is causing a salty problem.
Desalination plants around the world are producing enough brine waste to swamp an area the size of Florida with a foot of salty water every year, according to a U.N.-backed report released Monday.
The study by researchers from Canada, the Netherlands and South Korea warned that much of the brine is being dumped untreated into the sea, and some is laden with toxic chemicals, causing harm to sea life.
The authors called for better brine management, particularly in countries that rely heavily on desalination for their water needs, such as Saudi Arabia, the United Arab Emirates, Kuwait and Qatar.
“We know that water scarcity is increasing in many regions across the world due to increased water demands, which are associated with population increase and economic growth,” said one of the authors, Manzoor Qadir, assistant director of the United Nations University’s Canada-based Institute for Water, Environment and Health.
At the same, climate change is making the availability of freshwater less predictable, such as by changing the amount of runoff snow in some regions, he said.
The authors examined 16,000 desalination plants worldwide and found they produce 142 million cubic meters (5,014 million cubic feet) of brine each day, or 51.8 billion cubic meters a year. That’s about half more than previous studies had estimated, said Qadir.
The researchers called for better brine management, noting that studies have shown it can be used in aquacultures to boost yields of salt-tolerant species of fish, and the metals and salts contained in it — such as magnesium and lithium — could be mined.