SWRO Plant to make Sea Water Drinkable in Mumbai as Water Security Project Purifying seawater to make it drinkable involves desalination, a process that removes dissolved salts and minerals. Because seawater contains about 35,000 parts per million (ppm) of salt—nearly 100 times the safe limit—standard filters cannot make it potable. The transformation typically follows these four stages: 1. Intake and Pre-Treatment Raw seawater is drawn in and filtered to remove large debris, sand, and organic m