Kerala’s move to approach the National Green Tribunal against raising of the water level in Mullaperiyar dam is likely to boomerang on Kerala.
Environmental arguments similar to those against raising of reservoir level can be raised against lowering the reservoir level also.
In fact, changes to the ecosystem created by the dam and its water will be more pronounced while lowering the water level.
Kerala’s argument is that the raising of water level in the reservoir submerged nearly four decades old vegetation just above 136 feet level in Periyar Tiger Reserve. Lush vegetation including some specialised species have grown in the local environment created by lowering of the water level.
Now, let us look at what will happen if water level is reduced to 132 feet as demanded by Kerala at one point of time, or eventual phased decommissioning of dam. Lowering of the water level will result in the water table going down in many parts of Periyar Tiger Reserve. This would cause a relative drought conditions in many parts of the Sanctuary compared to the present situation and will loss of biodiversity and density of vegetation. The specialised species will not survive in its original location.
Environmental impact argument is something rejected by the Supreme Court in its 2006 verdict itself. However, Kerala tried to raise it again when Tamil Nadu challenged Kerala’s dam safety legislation before Supreme Court. For doing this, it commissioned a scientist from West Bengal, who produced a study report within a matter of weeks. The report had several errors and it was essentially a reproduction of arguments made by KFRI over which Kerala had argued its case earlier. Though these mistakes had been pointed out, Kerala went ahead with producing the author as a witness before the Court. During cross-examination, he admitted he had copied from the KFRI report. This meant that Kerala had no new argument or point to be presented before the Court. Now, Kerala is trying to revive its lost cause by approaching NGT. It is not even considering the fact that Supreme Court is above NGT.
In any case it will be a win-win situation for TN. If the NGT rejects Kerala’s prayer, TN will have another handle. If it upholds Kerala’s argument, TN can use it in future against lowering of the water level or decommissioning of the dam.
Kerala’s argument goes against what the State itself is proposing to do. The new dam it is proposing to build at Mullaperiyar will submerge some areas of Periyar Tiger Reserve. It is also seeking Central clearance for raising the height of Peppera dam near Thiruvananthapuram by at least three metres submerging about 80 acres of forest. Though the area submerged by increased water level in Mullaperiyar dam is larger than these, the forests that would be submerged by the new Mullaperiyar dam or augmentation of Peppara dam are part of ecosystems that are hundreds of years old. Obviously, much more value is to be attached to the latter.
Moreover, Kerala has done the same thing that TN is doing. Water level at Idukki reservoir had remained low for about three decades. Kerala carried out augmentation scheme under Idukki project to improve inflow. None batted an eyelid, when vegetation that grew over the period was submerged by increasing water level. Besides, the area being submerged at Mullaperiyar was leased to TN much before the enactment of environmental laws.
If we really care for environment (instead just using environmental arguments with the wrong belief that it will win a case in which the key issue is safety), we should demand environmental flows downstream of Mullaperiyar dam, abandon the proposal for new dam and seek phased decommissioning of the old dam.