A watershed is the area of land that drains to a common body of water. Water from rain and snow falls on the land surface and then drains or seeps into a wetland, marsh, stream, river, lake or into the groundwater. Water always runs to the lowest point in a watershed. Some water soaks into the ground, where it becomes groundwater. Other water flows across fields, forests, streets, parking lots and lawns before it flows into streams, rivers, lakes and estuaries. This water is called stormwater runoff. Watersheds are habitats for plants and animals and are places for people to live, work and play. We depend on water within our watersheds to supply drinking water and water for the food we eat. When stormwater flows across the land, it picks up eroded soil, leaves, oil, fertilizers, pesticides and anything else in its way. Sediment and chemicals can pollute the river, stream or lake where the water ends up. The health of a river basin is affected by the people living within its borders and the choices they make every day. People can take action to reduce the pollution that ends up in stormwater. Building ponds and wetlands helps reduce the amount of stormwater that runs off, which can reduce flooding. Other actions, like using rain barrels and preventing erosion, can conserve water that may be needed in a drought.