The unique idea of harnessing the westward flowing water of the Periyar river and diverting it to the eastward flowing Vaigai river was first explored in 1789 by Pradani Muthirulappa Pillai, a minister of the Ramnad king Muthuramalinga Sethupathy, who gave it up as he found it to be expensive. The location of the dam had first been scouted by Captain J. L. Caldwell, Madras Engineers (abbreviated as M.E.)
The concept of utilizing the westward flowing water of the Periyar river to divert it to the eastward flowing Vaigai river was first explored in 1789 by Pradani Muthirulappa Pillai, a minister of the Ramnad king Muthuramalinga Sethupathy, who abandoned it as he found it too costly. The site for the dam had been surveyed by Captain J. L. Caldwell, Madras Engineers (abbreviated as M.E.).