" About 71 percent of the earth’s surface is covered by water, and 97 percent of that water is saltwater. Only 3 percent is fresh water, and approximately two-thirds of that is frozen in glaciers and
polar ice caps. That means 1 percent of water on earth is readily usable. "

― Daisy Luther , The Prepper's Water Survival Guide: Harvest, Treat, and Store Your Most Vital Resource