There are two Coastal plains , The Western plains and The eastern plains.
A.The Western Coastal Plains:-The western coastal plains have rivers like Narmada ,tapti and mahi which forms estuaries which provide good sites for harbours.Mumbai and Marmagao have two of the best harbours of india.The western coastal plain is mainly divided into two sections:
1.Konkan 2. Malabar:-
The Coastal plains of maharastra and karnataka are called konkan Coast.
The Coastal plains of Kerala are called malabar Coast.
3.Lagoons:- a large number of backwaters are found along the Kerala coast .
B. The Eastern Coastal Plains:- The Eastern Coastal Plains includes the fertile deltas of the Mhanadi, Godavari, Krishna and Kaveri.
The Coastal plains of Tamilnadu and Andhra Pradesh are called Coromandel coast.
The Coastal plains of Orissa,and West bangal are called Circar Coast.