What is a Lagoon? (Geography)

A Lagoon is a shallow body of salt water (or brackish water) that is separated from the deeper, massive ocean by a thin, natural physical barrier.

This barrier acts like a protective wall. It can be made of sand (a sandbar), mud, pebbles, or even a living coral reef. Because of this barrier wall, the water inside the lagoon is very calm and peaceful, completely protected from the violent, crashing waves of the open ocean.

Most coastal lagoons are formed over thousands of years by ocean currents.

• The ocean waves constantly sweep up sand and dirt from the sea floor and dump it near the coast.
• Over time, this dumped sand builds up into a long ridge (called a sandspit or sandbar) that rises above the water.
• This sandbar eventually forms a wall, trapping a pool of ocean water behind it, creating a lagoon.

India has an incredibly massive coastline and is home to some of the largest lagoons in the world:

1. Chilika Lake (Odisha): This is the largest coastal lagoon in India and the second largest in the world! It is separated from the Bay of Bengal by a long sandy ridge.
2. Vembanad Lake (Kerala): The longest lagoon in India, famous for its backwater tourism and snake boat races.
3. Pulicat Lake: Located on the border of Andhra Pradesh and Tamil Nadu.