Earth has been called the Blue Planet due to the proliferation of water on its surface, but far less of that liquid is potable than the casual observer might think. According to the World Wildlife Federation, “Only 3% of the world’s water is fresh water, and two-thirds of that is tucked away in frozen glaciers or otherwise unavailable for our use. As a result, some 1.1 billion people worldwide lack access to water, and a total of 2.7 billion find water scarce for at least one month of the year.”

To make things even worse, water pollution puts potable water supplies at risk. “The United Nations World Water Development Report 2017” found that “globally, it is likely that over 80% of wastewater is released to the environment without adequate treatment. … Increased discharges of inadequately treated wastewater are contributing to the further degradation of water quality in surface and groundwater. As water pollution critically affects water availability, it needs to be properly managed in order to mitigate the impacts of increasing water scarcity.”