How much does a water desalination plant cost? Quora
Land based RO desalination systems for hotels and marinas (wall mounted) can produce up to 1400 gallons of drinkable water a day, and may cost 9750 USD. The Kurnell Desalination Plant should have provided Sydney, Australia with a substantial portion of its fresh water (but it started raining again), and its estimated construction cost was billion AU dollars, but it came in 60 million under budget.