Here’s one more reason to question the environmental viability of dams: another study shows that India’s dams are significantly contributing to greenhouse gas emissions in the form of methane, a gas which is not measured in the overall statistics for carbon emissions.
Both carbon dioxide and methane are released from the decaying vegetation of spillways, reservoirs and turbines of hydropower dams, but methane is twenty-three times more formidable in trapping heat than carbon dioxide.
India has approximately 4,500 dams, the third largest number of dams after the US and China. According to the study done by the National Institute for Space Research in Brazil, these dams emit an amount of methane that is equivalent to 850 million tonnes of carbon dioxide per year. Government authorities deny however that methane discharge from dams are a factor, stating that regular procedure is to remove vegetation from the reservoirs.
Dams in India are a sensitive and complex issue – they supposedly provide much-needed irrigated water to its enormous agricultural sector – which generates around 22 percent of the national GDP and employs 70 percent of the workforce on one hand – yet cause massive environmental destruction on the other.
For this reason, there has been intense opposition to dam-building from environmentalists and ordinary citizens alike, as dam projects also displace tens of thousands of impoverished people, submerge huge tracts of valuable farmlands and forests, while also destabilizing fragile aquatic ecosystems in the process.
Dams historically have been a huge point of contention in India. Most recently, a hunger strike was initiated by thousands of people from numerous villages affected by the Indira Sagar and Omkareshwar dams along the Narmada River.
As a developing nation, India is not required under the Kyoto Protocol to reduce its emissions, but it is clear that India’s mounting fuel consumption – which contributes to around four percent of carbon emissions annually and is now growing between two to three percent a year – will speed it along towards the dubious honours of becoming a major polluter, with its dams heavily adding to that equation.
Via ::Planet Ark
See also ::The Guardian
Image from Nadir.org