The Indian River Lagoon is an estuary. An estuary is a body of water where fresh and salt water meet and mix. Fresh water enters the estuary through rivers, creeks, canals, and rain. Salt water enters from the ocean through inlets, or narrow openings between barrier islands. The Sebastian Inlet is north of our school. The Fort Pierce Inlet is south of our school. 1. Visit an inlet. 2. Take photos. 3. Use the app of your choice to explain your trip to an inlet. 4. Add to Seesaw.