Freshwater is our planet''s most precious resource ¿ essential for life itself. Despite this fact, many people across our planet face difficulties finding safe, clean, potable water. A U.S. State Department report contends that the world''s thirst for water may become a human security crisis by 2040. The World Bank reports many developing nations face catastrophe from intensive irrigation, urbanization, and deteriorating infrastructure. Also, numerous reports contend that in many places un-treated wastewater is still released directly into the environment. This is particularly true in low-income countries, which on average treat less than 10% of their wastewater discharges.In short, we face three imminent challenges regarding freshwater: (1) demands by agriculture, cities, industry, and energy production are increasing; (2) severe pollution from various contaminants and growing withdrawals are limiting the capacity of waterways to dilute contaminants ¿ threatening human and aquatic lif