Wetlands, rivers, lakes, and coastal estuaries are all aquatic ecosystems—critical elements of Earth’s dynamic processes and essential to human economies and health.

Wetlands connect land and water, serving as natural filters, reducing pollution, controlling floods, and acting as nurseries for many aquatic species. Rivers, lakes, and estuaries serve as important transportation, recreation, and wildlife hubs.

Learning more about the ecosystems within your watershed—all the water in your region that drains to the same point—can help you better understand how everything is connected and what is at stake with freshwater overuse, pollution, and drought.