Why Don't Municipal Water Treatment Plants Use Distillation to Purify Water?

Distilling water ranks low on the list of public water treatment options because of its high energy usage, high cost and the amount of water wasted in the process. Approximately 5 gallons of water are wasted for every two treated. Drinking distilled water over an extended period of time can also cause health problems.

Distillation Process

• Distilled water, created by boiling and allowing the vapor to condense back into water, effectively removes 99 percent of everything in water, both good and bad. Primarily used in industrial settings, distilled water does not corrode equipment because it does not contain any minerals.

Soft Solvent

• Distilled water, like deionized water, is also known as a soft solvent. Because of its lack of ions, distilled water seeks to regain ions when it comes in contact with dissolvable or absorbable materials. When in contact with air, it pulls carbon dioxide ions into the water, causing the water to become highly acidic.

Drinking Water

• Distillation wastes more water than it treats. Not a cost-effective method of treating residential water, distilled drinking water provides no health benefits. Minerals needed for human consumption are missing from distilled water, and because it grabs carbon dioxide when in contact with air, the water becomes so acidic that it's not healthful for human consumption. Water for human consumption requires a 7.4 pH state.