The hydrologic cycle begins with the evaporation of water from the surface of the ocean. As moist air is lifted, it cools and water vapor condenses to form clouds. Moisture is transported around the globe until it returns to the surface as precipitation.
A watershed is all of the land that drains into the same location or body of water.
The Flint water crisis began in 2014 when the drinking water source for the city of Flint, Michigan was changed to the Flint River. Due to insufficient water treatment, over 100,000 residents were potentially exposed to high levels of lead in the drinking water.