What is our position on hydro-power generation vis-a-vis environment protection? Kindly explain.

Abdul Ashraf, Kozhikode, Kerala

HYDROELECTRIC power can be from run of the river projects that have very little, or no impoundment of water, or from dams that impound a large amount of water, and then use it for generating electricity. Run of the river projects have much lower environmental impact, even though the cumulative effects of a large number of run of the river projects on the same river could create significant impact. Because of smaller impact of run of the river projects, they have been regarded as environmentally more benign. Big dams store large quantities of water, create reservoirs, submerge lands and cause significant displacement of people. The environmental impact of such large dams is much greater than run of the river projects.  

Before we get into the pros and cons of hydroelectric power, let us look at some facts. As per World Register of Dams, there are 58,402 large dams in the world, out of which more than 5,000 dams are in India alone. Dams can be multipurpose – for irrigation, flood control and hydroelectric generation – or for a single purpose. About half of world's dams are single purpose. The Grand Anicut, Tamilnadu, was built by the Cholas in 2nd century AD (though extensively modified by the British in the 19th century) and is one of the oldest dams in the world. India has a rich history of civil engineering and building large dams going back to ancient times.

Reasons for building large dams is not just producing electricity, but flood control and irrigation. India gets rains in the monsoons – these are seasonal rains – and without storing water, we cannot use it in the dry season. With multiple cropping, irrigation has become more and more important. Flood control, as was in the case of Damodar, can be also of great importance. The annual flooding of rivers such as Hwang Ho in China – called China's Sorrow earlier – and Damodar used to create devastation. Producing electricity was, quite often, not the cause but the by-product of such large multipurpose projects.

However, introducing hydropower in a project, can lead to increasing the height of the dam, and cause much higher levels of submergence. One of the issues in Narmada was what should be the height of the dam, so as to retain most of the irrigation benefits, while reducing submergence, and therefore the displacement of people. The argument against the lowering of dam height by the Narmada authorities was that it would reduce electricity generation and therefore adversely affect the benefits.

More than the environmental impact, it is the displacement of the people that has led to large-scale resistance against big dams in the country. Coupled with displacement, has been the failure of the government in providing compensation to those who lose their land and livelihood, and land to the displaced farmers. Quite often, large dams have impact across multiple states, creating inter-state disputes. It is the failure of successive governments – both centre and state – that made people lose faith in government's promises of compensation and rehabilitation, leading now to widespread opposition to big dams.

There have been many arguments based on the dangers of a dam breaking and possible disasters. We believe that it is possible to build safe dams, and have been doing so for hundreds of years. It is possible that in earthquake prone areas, the cost of proper earthquake “proofing” can be high, but that is what needs to be considered in the design and costs of the project. Periodic safety studies are, and should be, a part of monitoring existing dams.

We do not believe that there can be a one-size-fit-all position rejecting all dams. Each river is a unique hydrological system and has its specificities. Any dam therefore requires an environmental impact assessment and a cost benefit analysis, taking both social and economic costs into account. We need to work out a more sophisticated analysis of such large projects than what we use today; big and complex projects are different from that of constructing, for example, a culvert by the public works department (PWD) and therefore, need a more complex analysis. We need to examine all the costs and benefits – what should be the height of the dam, the size of the reservoir, the corresponding displacement of the people, the benefits from irrigation and electricity generation, as well as a comprehensive rehabilitation plan for the people – in any assessment of big dams.

While electricity generation may have other options, irrigation relies on either surface irrigation – wells, ponds, and irrigation canals – or use of ground water that is fast depleting in many parts of the country.  Unlike surface irrigation, ground water resources have been created over centuries, and once depleted, cannot be recharged quickly. Surface irrigation, and therefore dams for irrigation purposes (or as one of its purposes) should continue to remain an option for India.

Finally, all forms of electricity generation have environmental impact. Burning fossil fuel – coal and oil – emit green house gases and lead to climate change. Nuclear plants store radioactive wastes, which we still have problems with in disposing safely. As we saw in Fukushima, they have the additional danger of accidents. Even solar and wind power have some environmental impact. Hydroelectric power, like wind and solar, is renewable, so does not have the kind of impact that burning fossil fuel or nuclear plants have, but it does have greater environmental impact than solar or wind. We need to examine the benefits as well as the impact – including possible hazards – of a specific form of energy, instead of a blanket opposition.