Fresh water is necessary for life. Freshwater resources are unevenly distributed on Earth's surface. The availability of fresh water affects how many organisms can live in an area.

Throughout this module, you will explore the distribution and uses of fresh water on Earth. The availability of fresh water depends on the local resources and composition of the underlying rocks and sediments. The sustainability of freshwater sources depends on the rates at which water is being removed vs. being stored. You will run experiments to explore water movement below Earth’s surface, predict water availability related to recharge and water use and hear from a hydrologist doing research on groundwater quality and availability. By the end of the module you will be able to explain how humans can maintain and replenish freshwater supplies long into the future.