Demanding the setting up of a Cauvery Management Board (CMB), farmer's organisations and political parties in Tamil Nadu staged protests on rail tracks on Monday.
In Thanjavur district, the police arrested several farmers who were protesting on the rail tracks.
In the state capital Chennai, Dravida Munnetra Kazhagam (DMK) leader M K Stalin led the party's protest at Perambur.
Similarly, members of the DMK, Congress and Marumalarchi Dravida Munnetra Kazhagam were arrested while they protested at different parts of the state.
Tamil Nadu and Karnataka have been at war since long over the sharing of Cauvery river waters.
On October 3, the Ministry of Water Resources filed an interlocutory application in the Supreme Court seeking modification of its September 30 order to constitute the CMB by October 4.
The Ministry, in its application, said that the CMB cannot be constituted by the October 4 deadline.