The government move to raise the reservoir level of Peppara dam in Thiruvananthapuram district tends to undermine one of the arguments of Kerala in the Mullaperiyar case. The reservoir level is proposed to be raised to increase the availability of water for augmentation of water supply to Thiruvanathapuram city.

In the Mullaperiyar case, Kerala had contended before the Supreme Court that raising of the water level in the Mullaperiyar (Thekkady) reservoir would affect the biodiversity of the Periyar Tiger Reserve, in terms of both vegetation and wildlife. However, the Court rejected the argument that higher water level would be detrimental to the environment.

However, the government subsequently constituted an expert committee to assess the ecological impact assessment of increase in water level at the Mullapperiyar Dam and submitted its report to the Supreme Court in a case filed by Tamil Nadu against Kerala's law that restricted raising of the water level in the Mullaperiyar Dam. The committee recommended against increasing the water level from 136 feet to 152 feet, which was the designed full reservoir level of the Mullaperiyar dam. (The full reservoir level was lowered to 136 feet in 1979 following concerns over the safety of the dam.) It said that any increase in water level would submerge a greater part of the critical grasslands of the Periyar ecosystem and thus harm the environment.

If one goes by the arguments raised by the expert committee and the government in the Mullaperiyar case, there is little ground for raising the reservoir level of Peppara dam. The Peppara Wildlife Sanctuary is part of the Agasthyakoodam Biosphere Reserve which is richer in biodiversity and endemicity than the Periyar Tiger Reserve. The areas proposed to be submerged by the raising of the reservoir level are locations frequented by elephants and habitat of many wild animals.

In the case of Mullaperiyar dam, 152 feet was the full reservoir level fixed more than 100 years ago. The Peppara dam was commissioned in 1983 and the wildlife sanctuary was notified in the same year specifying the reservoir level as 104.5 metres. It is claimed that this was a mistake and permission should be granted for raising of the water level to 110.5 metres as was intended originally.

The Forest (Conservation) Act, which was enacted in 1980, mandated Central clearance for diversion of forests for non-forestry purposes which had been denied twice for raising of the water level of Peppara Dam. The question was placed before the State Board for Wildlife again in recent years, and the Board suggested that the level may be raised by one metre, and its impact studied before raising it by six metres. (A sub-committee of the Board, which studied the issue, feared serious harm to biodiversity.) This proposal, however, is not acceptable to the government and the Board has been asked to reconsider the matter again. Even if the State Board approves it, the National Board for Wildlife too would have to approve the proposal. Stringent guidelines exist for the Board in granting clearance for diversion of protected areas.

During discussions Chief Minister Oommen Chandy had with Union Minister of State for Environment and Forests Jairam Ramesh last week, Mr. Ramesh had said that he would help in getting clearance from the national Board. The Ministry would also approve it subsequently. But, the ball was now in the State's court. Mr. Chandy has, however, portrayed this as approval from the Ministry.

Even if the approval comes through, the shutters of the Peppara reservoir, which are to be raised to increase the water level, are in disrepair. These would probably have to be repaired or replaced. By the time the work is done, half the normal life of the dam would be over.

Keywords: Peppara dam