Do hydel units cause pollution?
From S.P. Sharma and Rakesh Lohumi
Tribune News Service

SHIMLA, Sept 20 — The Centre's move to take out hydroelectric projects from the purview of the Water (prevention and control of pollution) Cess Act, 1977 has generated a debate whether or not hydel generation has an adverse impact on the environment.

The Act provides for imposition of cess on water utilised by 29 specified categories of industries and local authorities.

Hydel generation was brought under the purview of the Act in April, 1993, after carefully considering its environmental fallout in the ecologically fragile hills.

Subsequently, the Centre made formulation and management of environment impact assessment plan mandatory in respect of the specified categories of projects, including hydel power projects, indicating that it also considered these hazardous to the environment.

While the Himachal Pradesh Pollution Control Board was in the process of levying the cess on hydel projects in the state, the Union Ministry of Environment in a surprise development informed the board that these projects were being excluded from the purview of the Act.

Thereafter, the Centre took a decision to delete the hydroelectric projects from the list of specified industries covered under the Act on the recommendations of the Parliamentary Standing Committee.

The committee in its brief report observed that hydel generation was a clean method of producing power. It brushed aside all arguments advanced by the Ministry to convince that hydro storage projects affected the quality of water and environment by terming them "too technical" in nature.

The committee reached the questionable conclusion that hydel projects did not cause any "real pollution" which could be dealt with by the state pollution control board utilising the cess collected.

It also expressed apprehensions that levying the cess on this particular category of projects would raise the cost of generation which not only affect big industries, but also small consumers. Besides, there has been no unanimity among various states on the issue.

While the neighbouring states like Punjab are opposed to the levying of the cess, Himachal Pradesh, where most of the inter-state hydel projects are located, sees a major source for raising funds through the proposed cess.

The proposal has been kept in abeyance by the Centre on the plea of the Himachal Government and the matter has been referred back to the Parliamentary Standing Committee.

This development has activated the states which were against the cess and were mounting pressure on the Centre to go ahead with the move to exclude hydel generation from the purview of the Act.

Some leaders of Punjab have even mooted the idea of imposing a floods cess on hill states from where the rivers originated and flooded the plains.

Himachal Pradesh on the other hand has termed it as a retrograde step which goes against the avowed objective of the Act — to augment resources of the central and state pollution control boards for prevention and control of water pollution. Exclusion of hydel generation would have a highly adverse effect on the resources of the fund-starved state and would put a brake on its efforts to combat overall ecological deterioration.

The HP Pollution Control Board has conducted a number of studies and also provided scientific data available from research conducted elsewhere in the world to support its contention that projects were hazardous for environment.

The studies reveal that impounding of water leads to a build-up of harmful gases like hydrogen sulphide and mathane produced due to anaerobic decomposition of biomass in the bottom sediment of reservoirs. Besides, it also leads to a decrease in dissolved oxygen levels and an increase in concentration of carbon dioxide, nitrogen and other gases which affected aquatic life.

Siltation choked recharging of acquifers causing changes in ground water pattern. It was also observed that conductivity and alkalinity decreased with the depth and concentration of nitrates, phosphates and other mineral salts increased.

All these factors not only rendered the water unfit for aquatic life, but also contributed to the global warming phenomenon. A large reservoir of the size of the Bhakra or the Pong can create a "green house" effect comparable to that of an equivalent thermal power plant.

The state emphasised the fact that all these adverse effects could be prevented by taking appropriate remedial measures which would not only increase the efficiency of power plants, but also prolong their life span which is threatened by excessive siltation at present. But funds were required to implement these measures and these could be raised only by imposition of water cess.