Thiruvananthapuram: Kerala Chief Minister Oommen Chandy on Thursday appealed to his Tamil Nadu counterpart Jayalalithaa to take urgent steps to reduce the water level in Mullaperiyar Dam to 120 feet from the present 136.5 feet in view of the "threat" posed by the structure to millions of people living downstream.

In a letter to Jayalalithaa, Chandy said fears about the weakness of the 116-year-old dam had increased since the area around the site had been shaken by as many as 26 tremors in the last five months alone.

This is the first time that Chandy has written to Jayalalithaa after escalation of tension over the Mullaperiyar issue.

The situation was "so serious" that it warranted immediate steps like lowering the water level in view of the safety of the people without waiting for the verdict from the Supreme Court and the Empowered Committee, which had been considering in detail legal and technical aspects of the issue, he said.

Chandy said it would be difficult for the state government to remain silent when millions of people were living in great anxiety.

Maintaining that Kerala had no intention to curtail water to Tamil Nadu from the present level, the Chief Minister said the state expected Tamil Nadu to take urgent steps to ensure safety of four districts of Kerala.

The area had been shaken by 26 tremors since July 2011. Experts had said that if a tremor measuring six on the Richter scale rocked the area, the dam would be in danger.

Such a scenario could spell dangerous consequences to millions of people living in Idukki, Kottayam, Pathanamthitta, Alappuzha and Ernakulam districts, he said.

The water level at Mullaperiyar Dam is now at 136.5 ft, slightly above the maxium permissible storage level of 136 ft. The dam, located in Idukki district of Kerala, is under the control of Tamil Nadu and meets the irrigation needs of farmers in southern districts bordering Kerala.