Ansupa Lake is the largest freshwater lake of Odisha situated in Banki sub-division of Cuttack district and has its fame from time immemorial for its scenic beauty, biodiversity, and natural resources. The wetland is an oxbow lake formed by River Mahanadi and is spread over an area of 231 ha, surrounded by small hillocks namely Saranda, Bishnupur, Dhangarh, and Betla pahara. The lake is connected with Mahanadi on its southern side with a channel known as “ Kabula Nala” through which floodwater of Mahanadi enters the lake. The wetland is home to at least 194 species of birds, 61 species of fishes and 26 species of mammals in addition to 244 species of macrophytes. The wetland provides a safe habitat to at least three threatened bird species- Rynchops albicollis (EN), Sterna acuticauda (EN) and Sterna aurantia (VU) and three threatened fish species- Clarias magur (Clariidae) (EN), Cyprinus carpio (Cyprinidae) (VU) and Wallago attu (VU). Ansupa lake sustains the freshwater demands of the surrounding areas and also supports the livelihood of the local communities through fisheries and agriculture. The wetland has immense recreational and tourism potential as it is a major wintering ground for migratory birds and is also known for its scenic beauty.

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.