Large Dams: Boon or Bane!

Look what I found, a synopsis I wrote for a presentation at a techfest at college...

LARGE DAMS: BOON OR BANE?
Large dams have been regarded as icons of progress for long now. For many they symbolize the victory of man’s genius over nature. But isn’t it time to assess whether all that dams promise have been realized?
Dams, besides the creation of storage and head to generate electricity, are meant to supply water for agriculture, industries and households, to control flooding, to assist river navigation and to provide recreational facilities.
The works of many researchers show that dams while unable to fulfill these minimal functions cause extensive damage to ecosystems and humans. Construction of large dams causes the submergence of large tracts of land displacing millions of people and destroying acres of forestland. Yes, they do eliminate normal annual floods but they also increase the severity of flash floods. River navigation is almost made impossible by dams because most have been constructed without locks, which are rather expensive in construction. Traditional river-users are at a loss because their vessels are not suitable to be used over dangerous reservoirs containing drowned trees and other obstacles. Water for the purpose of irrigation in most of the cases lost on its way due to improper distribution systems and heavy losses in them. Drinking water is yet another thing. Dams often affect water quality adversely due to algal blooms and other parasitic beings like snails, mosquitoes, which flourish in the reservoir waters. Also faulty systems drink up most of the ‘better’ water available for supply. Recreation is rendered dangerous because downstream recreation activities may be flooded on release of the reservoir waters. Construction of dams fragments riverine ecosystems by isolating species living upstream and downstream. Estuaries are also at a loss as dams curtail the amount of nutrients dumped in it. Overall, Major dams can be regarded as a huge, long-term and largely irreversible environmental experiment without a control.
The need of opposing large dam construction is strengthened by the knowledge that most of the functions supposed to be fulfilled by dams can be met in other ways. Some of the sensible alternatives to building large dams are: Proper water shed management, rain water harvesting, traditional uses of irrigation, uses of other renewable sources of energy like wind, geothermal, tidal & solar energy, using check dams, harvesting the floods, water harvesting by storing water under ground to prevent surface evaporation and replenishing watersheds, and last but not least by encouraging small hydro, for a small trickle of water and a scope of hills are all it needs.
Since these alternatives have been found to be sustainable and efficient at many places we can employ them to reduce if not to complete nullify the harm the Mega dams have already caused on our fragile ecosystem and lives.

It was in 2003 and I was deeply influenced by the excellent book 'Silenced Rivers' by Patrick McCully. As for the presentation, I was immature, lacked preparation, had only big spirit, so the presentation went well but on the question answer session I was poorly prepared, our geotechnical engineering teacher asked me what kind of dam Idukki dam was, I didn't know...
But I did the same at a Friday student's meeting of WWF once and it was great! :)
Well, guess it depended on good preparation and the right audience!