Taking Action in India on Downstream Impacts of Dams

Parineeta Dandekar and Samir Mehta

india is on a large-dam building spree, with more than 5,100 large dams already blocking almost all of its important rivers, and more to come. These dams have had a profound negative impact on communities and ecology upstream and downstream. While promised benefits of these dams (irrigation, hydropower or flood control) have been overstated, numerous interrelated and complex negative impacts have simply not been studied or documented. Nonetheless, communities and ecosystems continue paying huge prices of these impacts.

One neglected aspect of India’s dam-building spree is the huge downstream impact of dams. Dams completely change the nature of the river downstream, severely affecting communities dependent on the river for drinking, irrigation, fishing, transport and ecosystem services. In Northeast India, where an army of large hydropower dams is planned, in certain rivers daily water level fluctuation downstream of some dams is estimated to be over 13 feet. Communities are being warned to keep off’ their rivers! The need for strong advocacy to stall and mitigate these disastrous impacts cannot be more urgent.

In this context, International Rivers and Save Western Ghats Movement jointly organised a three-day meeting on the downstream impacts of dams in the global biodiversity hotspot of the Western Ghats, India. It was a first meeting of its kind in the country where the extensive downstream impacts of dams were discussed in detail by a range of stakeholders. There could not have been a better venue for such a workshop than the banks of Jog Falls on the River Sharavati. Jog is the highest untiered waterfall in India, six kilometres downstream of the Linganmakki Dam. The falls and river have been reduced to a trickle of their former self, with huge negative impacts on the unique ecology and sociology of the downstream region.

The 30 participants, representing 16 organizations, came from diverse streams, like ecology, sociology, hydrology, activism, academia and law. Participants shared their studies and experiences on dam safety, environmental flows, species loss due to upstream dams, and other relevant topics. One young, anguished ecologist said, “My studies tell me that we have lost several species even before we could record them.”

The most touching speakers were the fishermen and farmers who shared their difficult stories of lives torn apart by dams. Rajesh, a traditional fisherman from the dammed Neyyar River in Kerala, lamented that his son cannot be a fisherman, because since the dam there have been no fish to catch.

Ritwick Dutta, an eminent environmental lawyer, deplored the lack of information shared with civil society. He stressed the importance of building evidence and presenting the right ecological information as an effective tool in the fight against unsustainable dams.  Some destructive dams, he said, could have been halted if crucial information about their impacts on certain endangered and threatened species had been collated and presented in Court. This was an important lesson for all.

Participants also wrestled with the definition and scope of “downstream.” It was accepted that downstream impacts do not stop at a certain pre-defined distance, but depend on various factors like the geomorphology and sediment load of the river, and patterns of settlement and the size of the river-dependant population. In vew of failed institutions and shoddy environmental governance, a central role for communities and NGOs was recommended. It was unanimously decided that the group will advocate with the Ministry of Environment and Forests for inclusion of the study of downstream impacts in Environment Impact Assessment reports of proposed dams. Strong advocacy becomes all the more urgent in the face of numerous dams coming up in the country’s northeast.

The way forward looks hard but clear. Many organisations have enthusiastically come forward to take on crucial tasks – for example, doing a pilot study of specific river basins in Western Ghats to study the downstream impacts of dams, mapping the ecological status of river basins in the region, and working on a status report on the downstream impacts of dams in the Western Ghats.

The workshop has been a great start in initiating new discussions and bringing diverse stakeholders together. In the end everyone asserted the need to highlight downstream impacts of dams in basin-level planning, and in their individual work. They underlined the need for creating teams of experts and community representatives for assessing and mitigating downstream impacts of dams in this global biodiversity hotspot. Representatives from northeast India stated they would hold a similar workshop in their region later this year.

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