Reverse Osmosis is a process through which water is forced through a semi-permeable membrane, leaving unwanted pollutants and contaminants behind. The process uses no chemicals or electricity and is the most effective technology known for the improvement of drinking water. Most house filtration systems will likely remove less than 20% of contaminants in tap water. Reverse osmosis systems can remove up to 99.9% of contaminants. At Vintner's Cellar we use Reverse Osmosis water in all our wine making and provide this high quality water for sale at the front of the store.