An estuary is where freshwater and salt water combine and meet into one. It is where a river and a lagoon meet and transitions between rivers and seas. Estuaries are shallow protected bays. The sea water is mixed with fresh water when met coming from the land. When the water mixes the salt water will move along the estuaries bottom while the fresh water flows downstream into the surface of salt water oceans and this is considered the "transition zone" where there are different layers in the ocean. Estuaries have three different sections, the first section is where the rivers, lagoons, or bays meet saltwater, there is generally more fresh water then salt water. The second zone is where the waters are mixed equally. And the third section is where the water slowly starts to flowing into the ocean. The color of the water is different then regular...