The impounded water of the Koyna Dam though has submerged a significant amount of Rain forest of the Western Ghats, it has helped a lot to the surrounding forest by supplying water all round the year.
Hence a wide biodiversity of plants and animals is observed in the evergreen forest surrounding the river.
The legendary source of the river is a spout from the mouth of a statue of a cow in the ancient temple of Mahadev in Old Mahabaleshwar.
Legend has it that Krishna is Lord Vishnu himself as a result of a curse on the trimurtis by Savitri.
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