Do Desalination Plants Increase Ocean Salinity?
Cities around the world are building desalination plants to obtain drinking water. If so, they may be on their way to becoming like the Great Salt Lake. Joyce Welpott, Hilton Head, South Carolina  The monetary cost of desalinating water is decreasing, but the environmental cost is high. First, the process requires a huge amount of energy, adding to global warming. And it increases the salinity of the oceans as it removes water for drinking and leaves the salt. Also, the process wreaks havoc on local marine life when the salty sludge is discharged back into the sea indiscriminately. So efforts are underway to improve the process.