Odisha Chief Minister Naveen Patnaik on Saturday requested his Chhattisgarh counterpart Raman Singh to immediately open the gates of the Kalma barrage, which, Patnaik claimed, were closed unilaterally by the Chhattisgarh government.

The Odisha Chief Minister said the gates of Kalma barrage had been closed, stopping the free flow of water to the downstream areas even though constructions there by the neighbouring state were challenged in the Supreme Court.

"The reports available with my government definitely convey that your government has gone ahead and closed the gates of Kalma barrage, stopping the free flow of water. This unilateral decision to stop the flow has caused distress situation in the downstream areas in my state, inter alia, affecting the drinking water needs," Patnaik said in a letter to Singh.

He said the people in the districts of Sambalpur, Jharsuguda, Bargarh and many other districts had been affected and there was widespread unrest due to the unilateral action of Chhattisgarh in stopping the free flow of water in the Mahanadi river.

"This unrest may go out of hand if free flows downstream of Kalma barrage in Mahanadi river are not restored immediately," said the Chief Minister.

He said the officials of the Odisha government had already informed the Chhattisgarh government about the problems caused to the downstream areas in Odisha.

"I emphatically state that this unilateral action of your government of closing the gates of Kalma barrage and stopping free flow of water is wholly contrary to the inter-state riparian rights as per the 1945 understanding (under the Chairmanship of Dr.B.R. Ambedkar) when the Hirakud Dam was planned," said Patnaik.

The Chief Minister said the state government had moved an inter-state tribunal and filed an original suit in the Supreme Court along with an interlocutory application to restrain Chhattisgarh from proceeding with the construction of six barrages including the Kalma barrage.

"When the matter is pending before the apex court, it is expected of your government to maintain status quo regarding free flow in Mahanadi river at Kalma barrage," he added.