The simple answer is that glaciers and icecaps hold the majority of Earth's fresh water. This means that almost 69 percent of all of the fresh water on the planet is locked away in frozen places, basically unreachable. Where is the rest of our fresh water? 30.1% is found in ground water. If you're paying attention to the math, that only leaves just over one percent of the planet's fresh water in surface areas, like lakes, where living things can use it. It is amazing that, with only 2.5% of our total water on Earth being fresh water, such a small percentage of an already tiny percentage is responsible for sustaining us. The reference links provided break down the numbers even further to provide a closer look.