Water is an essential resource that is required by all life on Earth. Hydrology is the part of science with earths water and land. This relates to watersheds. Watersheds include land and water and The hydro logic cycle is basically a watershed.
A watershed is something that everyone lives in. It is the point of a river, lake or ocean were the water meets the land. This could of effected the Flint Michigan water crisis. The water could have gotten dirty from rubbing against dirty land.
This link describes facts on this crisis. The Crisis started first with the city loosing money. They tried to save money and they changed their water system. They used to get there water from lake Huron but to save money they changed to Flint river. This waterwas not cleaned and Led was found in the water.