Coastal Regulation Zone (CRZ) is a term used in India to refer to the coastal areas of creeks, seas, bays, rivers, and backwaters that get affected by tides up to 500 meters from the high tide line (HTL) and the land area between the low tide line (LTL) and the high tide line. The CRZ rules and regulations have been formulated with the objective of protecting coastal ecosystems by regulating human and industrial activities near the coastline. The coastal land up to 500m from the High Tide Line (HTL) and a stage of 100m along banks of creeks, lagoons, estuaries, backwater, and rivers subject to tidal fluctuations is called the Coastal Regulation Zone (CRZ). The CRZ along the country has been placed in four categories: CRZ-1, CRZ-2, CRZ-3, and CRZ-4. The categories are defined as follows:

• CRZ-1: These are ecologically sensitive areas, such as mangroves, corals/coral reefs, sand dunes, national parks, marine parks, sanctuaries, reserve forests, wildlife habitats, etc. The coastal regulation zone areas in CRZ 1 are situated between high tide lines and low tide lines.
• CRZ-2: These areas are urban areas located in the coastal areas. Under Coastal Regulation Zone (CRZ) Notification 2018, the floor space index norms have been unfrozen.
• CRZ-3: Rural and urban localities which fall outside the 1 and 2. Only certain activities related to agriculture and even some public facilities are allowed in this zone.
• CRZ-4: This lies in the aquatic area up to territorial limits. Fishing and allied activities are permitted in this zone. No Solid.

State governments are responsible for preparing Coastal Zone Management Plans (CZMP) and implementing the CRZ rules through their respective Coastal Zone Management Authorities.