Mullaperiyar: genesis of a dispute

Understanding the unique complexities that have led to uneasiness in Tamil Nadu-Kerala water sharing.

Updated - November 28, 2021 08:25 am IST

Published - August 25, 2018 09:56 pm IST - CHENNAI

 The Mullaperiyar dam, located in Kerala’s Idukki district, is operated and maintained by Tamil Nadu for meeting the drinking water and irrigation requirements of five of its southern districts.

The Mullaperiyar dam, located in Kerala’s Idukki district, is operated and maintained by Tamil Nadu for meeting the drinking water and irrigation requirements of five of its southern districts.

The colonial-era Mullaperiyar dam has again become a source of friction between Tamil Nadu and Kerala. Though the original dispute was over the appropriateness of the dam’s water level, Kerala, already reeling under severe adverse impact from floods, has surprised everyone this time by accusing Tamil Nadu of having carried out “sudden releases” of water. This, Kerala says, forced it to discharge more water from the downstream Idukki reservoir, about 40 km away from Mullaperiyar, which has been cited as one of the causes for the “deluge”. In Kerala’s assessment, Tamil Nadu should have heeded its request immediately and lowered the water level in Mullaperiyar to 139 ft for moderating floods.

‘Far less’

Tamil Nadu, on its part, has defended its position and stated that, well before shutters of the Mullaperiyar were opened in the early hours of Independence Day (August 15), excess water was being discharged through the flood gates of several dams in Kerala. Besides, compared to about 36 thousand million cubic feet (TMC) of water released from the Idukki and Idamalayar dams in the Periyar basin from August 14-19, the amount of water released from Mullaperiyar at the same time was hardly 6.65 TMC, which was “far less” than the quantities of water that flowed from the other two dams. Mullaperiyar, the safety of which has been confirmed by experts on several occasions, has enough provision to handle flood flows: this is how Tamil Nadu justified its stand, and denied the charge made by its neighbour.


For those uninitiated into the history of the Mullaperiyar, here are some facts: the dam, located in the Idukki district of Kerala, is operated and maintained by Tamil Nadu for meeting the drinking water and irrigation requirements of five of its southern districts. As a sequel to an agreement signed between the then Travancore and Madras governments in October 1886, about 8,000 acres was leased by the former to the latter for the execution of the dam project. The dam was built over the period from 1887 to 1895.

Troubles begin

Everything went smoothly for nearly 80 years. But, in 1979, a row erupted over the safety of the dam. Consequently, in November 1979, a tripartite meeting chaired by the then head of the Central Water Commission, K.C. Thomas, decided that water level had to be brought down from the full reservoir level of 152 ft to 136 ft, in order to enable Tamil Nadu carry out dam strengthening works. By mid-1990, Tamil Nadu started demanding restoration of the water level in the Mullaperiyar as it had completed the task assigned to it. When no consensus was reached through negotiations, the Supreme Court was approached. In two separate judgements, in 2006 and 2014, the apex court held that the water level be raised to 142 ft.


It is against this background that the latest controversy has to be viewed. An element of uneasiness has entered the ties between Tamil Nadu and Kerala on the subject of water. The equation between the two States is far more complex than those of Tamil Nadu with Karnataka. With Kerala, Tamil Nadu has issues on several river waters, such as Parambikulam-Aliyar, Siruvani of the Bhavani sub-basin, Neyyar, and the proposal for linking the Pamba and Achankovil rivers of Kerala with Vaippar of Tamil Nadu. But, in the case of Karnataka, Cauvery is the only river to be considered.

As for events concerning the present Kerala floods, there has been criticism in certain quarters that the authorities in the State delayed the release of surplus water until the end. Officials of Tamil Nadu, too, are of the view that it was their counterpart that had “mismanaged” the release of water from its reservoirs, and only a “negligible amount” of water flowed from the Mullaperiyar to Kerala.


What is being overlooked in the current discourse is that Kerala, after a gap of five years, is experiencing a bountiful southwest monsoon (June-September). As a matter of fact, between 2010 and 2017, there was only one excess monsoon — in 2013. There were three deficit years (2012, 2015 and 2016), while the remaining four years had a ‘normal monsoon’. Even in the ‘normal’ years, two years recorded a negative value of departure for rainfall. So, Kerala’s water managers were under enormous pressure to store as much water as possible. This could have possibly come in the way of their judgement in commencing the release of water even at the beginning of August, when the storage in two important dams — Idukki and Idamalayar — was a little more than 90% of their capacity. According to an August 19 report by the Meteorological Department, in all of 35-odd major reservoirs in Kerala, storage was close to the full reservoir level (FRL) by the end of July, and there was no buffer storage left to accommodate heavy inflows from August 10.


Tendency to store

Indeed, the tendency to store water to almost the full level of reservoirs is becoming a norm among water managers across States. In mid-July, Karnataka, too, started releasing surplus waters from the Kabini and Krishnaraja Sagar dams on the Cauvery system only when it knew that it could not hold any more water. Fortunately, the Mettur dam in the Salem district of Tamil Nadu is big enough to accommodate all the flood flows. For the last one month, Mettur, too, has been releasing excess water flows. In December 2015, Tamil Nadu also faced criticism for delaying the release of surplus water from the Chembarampakkam tank, causing floods in Chennai.

In the current battle over the Mullaperiyar, the Supreme Court has come Kerala’s rescue by telling Tamil Nadu to keep the water level in the dam at 139 ft till the end of August. But Kerala and Tamil Nadu must introspect seriously over their respective positions and avoid acrimony while protecting their interests.

0 / 0
Sign in to unlock member-only benefits!
  • Access 10 free stories every month
  • Save stories to read later
  • Access to comment on every story
  • Sign-up/manage your newsletter subscriptions with a single click
  • Get notified by email for early access to discounts & offers on our products
Sign in


Comments have to be in English, and in full sentences. They cannot be abusive or personal. Please abide by our community guidelines for posting your comments.

We have migrated to a new commenting platform. If you are already a registered user of The Hindu and logged in, you may continue to engage with our articles. If you do not have an account please register and login to post comments. Users can access their older comments by logging into their accounts on Vuukle.