Members of various other organisations who opposed the project also joined the fast.
Vaiko claimed that the Mullaperiyar and Idukki dams would be affected by the project and he had spoken to the Kerala Chief Minister about it.
He claimed that farm lands would become barren if the project was implemented and hence Tamil Nadu and central government should drop it.
He also said a 'human chain' protest would be held at Thanjavur on April 7 to protest proposed check dams across the Cauvery river in Karnataka.