These wetland include

Wetland	Specifications
Nanjarayan Bird Sanctuary (Tamil Nadu)	Nanjarayan Lake a large shallow wetland named after King Nanjarayan (who restored and repaired it). It depends on heavy rain water flow from Nallar drainage. Acts as feeding and nesting habitat for resident and migratory birds; water source for agricultural purpose.
Kazhuveli Bird Sanctuary (Tamil Nadu)	Brackish shallow lake located on Coromandel Coast in North of Pondicherry. Connected to Bay of Bengal by brackish Uppukalli creek and Yedayanthittu Estuary. Lies in Central Asian Flyway of migratory species. Breeding ground for birds, fish; source for aquifer recharge; houses highly degraded mangrove patches containing Avicennia species
Tawa Reservoir (Madhya Pradesh)	Located inside Satpura Tiger Reserve and borders Satpura National Park and Bori Wildlife Sanctuary. Constructed at confluence of Tawa and Denwa rivers. River Tawa (left bank tributary of Narmada River) originates from Mahadeo Hills. Rivers Malanni, Sonbhadra and Nagdwari are major tributaries of reservoir.

About Wetland

An area of land that is saturated with water.
Wetland must meet at least 1 of 9 criteria like regularly supports 20,000 or more water birds, or conserving biological diversity etc.
Now, total Ramsar Sites in India is 85. Tamil Nadu has maximum Ramsar Sites.