Vedanthangal wetland and surrounding 5km zone are notified as Vedanthangal Bird Sanctuary. This bird sanctuary is one of the oldest birdprotected areas in the country as well as in the State of Tamil Nadu. The sanctuary is located in Maduranthagam Taluk of Chengalpattu District (erstwhile Kancheepuram). It is located at 12o28’ 54” N and 790 51’ 6” E. The wetland is 122 m above Mean Sea Level and situated 48 km inland from the Bay of Bengal. The sanctuary comprises a small irrigation tank with an area of 40.348 ha in Vedanthangal village and the surrounding 5 km zone around the lake. The longer axis of the lake is 600 m, oriented towards the east-west direction and a 4 m high earthen bund lies along the western boundary to a distance of 935 m. Initially, Vedanthangal wetland was declared as Reserve Land as per Section 26 of Madras Forest Act, 1882 vide G.O.No.1961, Forest & Agriculture dated 4.6.1962. Rules for protection of the Vedanthangal wetland were framed as per Section 26(c), (e) & (f) of Madras Forest Act vide G.O.Ms.No.1961, Food & Agriculture Department dated 03.03.1962. Subsequently, the wetland and the surrounding 5 km zone were declared as Vedanthangal Birds Sanctuary as per Section 18 of Wildlife Protection Act in 1996, and further, final notification of Sanctuary under section 26A of Wildlife (Protection) Act, 1972 was issued vide G.O.Ms.No.199, Environment & Forest Department (FRV) dated 08.07.1998. In section 18 as well as section 26A notification of the Vedanthangal Sanctuary, area and boundary description of the Lake is only mentioned but not of the surrounding 5 km zone. The Sanctuary consists of distinctive species of flora viz., Barringtonia acutangula, Acacia nilotia, and Terminalia arjuna. This freshwater wetland is a people-protected water bird area, the history of which goes back to centuries where local people have been protecting this heronry and in return, have been benefited by the manure-rich water from the lake that increases the agriculture yield multifold–Liquid Guano Effect. This site is also recognized internationally, as an Important Bird and Biodiversity Area (IBA) with a code IN284, Criteria A1, A4iii. It belongs to the Coromandel Coast biotic province.

A wetland should be considered internationally important if it contains a representative, rare, or unique example of a natural or near-natural wetland type found within the appropriate biogeographic region.

A wetland should be considered internationally important if it supports vulnerable, endangered, or critically endangered species or threatened ecological communities.

A wetland should be considered internationally important if it supports populations of plant and/or animal species important for maintaining the biological diversity of a particular biogeographic region.

A wetland should be considered internationally important if it supports plant and/or animal species at a critical stage in their life cycles, or provides refuge during adverse conditions.

A wetland should be considered internationally important if it regularly supports 20,000 or more waterbirds.

A wetland should be considered internationally important if it regularly supports 1% of the individuals in a population of one species or subspecies of waterbird.

A wetland should be considered internationally important if it supports a significant proportion of indigenous fish subspecies, species or families, life-history stages, species interactions and/or populations that are representative of wetland benefits and/or values and thereby contributes to global biological diversity.

A wetland should be considered internationally important if it is an important source of food for fishes, spawning ground, nursery and/or migration path on which fish stocks, either within the wetland or elsewhere, depend.

A wetland should be considered internationally important if it regularly supports 1% of the individuals in a population of one species or subspecies of wetland-dependent nonavian animal species.