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Dam frenzy fails to notice environmental concerns
NEW DELHI, 5 May 2013: Housed in the ministry of environmentand forests is a quasi-independent body whose job it is to scrutinise every hydel project for environmental damage. In its six years, the hydel environmental assessment committee (EAC) has evaluated 262 hydropower plants and irrigation projects, according to a February 2013 study by theSouth AsiaNetwork on Dams, Rivers and People (SANDRP), a Delhi-based anti-dam organisation. It hasn’t rejected a single one.
The prospect of a similar rate of clearance in Arunachal is alarming researchers, who say projects are being cleared on a case-by-case basis, without fully understanding the possible cumulative environmental fallout of such a large build-up.
Take what will happen to the Lohit, which flows out of Arunachal and into the Brahmaputra, when the Lower Demwe Hydro Electric Project on it switches on. According to the project’s environmental impact assessment (EIA) report, the Lohit’s flow is around 463 cubic metres per second (cumecs) in winter, 832 cumecs in summer and 2,050 in the rains. (A three cumecs flow is akin to aTata Nanopassing you every second.)
This will change once the dam comes up. For up to 20 hours a day, says the report, the dam will trap the river, releasing just 35 cumecs of water. The remaining will be released to spin the turbines only when demand for electricity rises in the evening. At that time, the river’s flow will expand to 1,729 cumecs. As the reservoir empties out,the riverwill again shrink to 35 cumecs.
This is palpably new. River flows ebb and rise over months. “But now, what was an annual variation will now be a daily variation,” says MD Madhusudan, a biologist with Mysore-basedNature Conservation Foundation. And this is from just one dam; each of the eight tributaries emptying into the Brahmaputra has multiple dams coming up.
To gauge their combined impact, rifle through the EIA report for the Jaypee Group’s Lower Siang Project. If water from the three terminal dams on the Lohit, Subansiri and the Siang rivers reaches the floodplains at the same time, the Brahmaputra’s height will fluctuate daily by 2-3 metres as far as 65 km downstream. This unpredictability of flow will affect fishing communities and those farming in the Brahmaputra’s floodplains.
There are other concerns. Multiple dams are coming up on each river. Take the Lohit, where the distance between six dams is 1 km, 9.5 km, 1.8 km, 3.8 km and 1.8 km, respectively. There are no authoritative studies on what such clustering portends for a river or how they will behave during a quake.
This part of the country is rocked by one earthquake over 8 on the Richter scale once every 100 years or so. “The largest quake in this area was 8.7. Now, there will be a series of cascading dams, each with a small reservoir, on each river,” says Chandan Mahanta, a professor teaching environmental engineering and engineering geology at IIT Guwahati. “These are things people have not seen. We need more simulation.”
“The issues surrounding these dams are very different from those relating to dams in the plains,” adds Dulal Goswami, a former member of the hydel EAC. “There, the main issues are relocation, rehabilitation and inundation. Here, the issues are seismicity, landslides and flashfloods. ” In a paper published in Science magazine this January, R Edward Grumbine, a professor at China’sKunming Institute of Botany, and Maharaj K Pandit, a professor at Delhi University’s Centre for Interdisciplinary Studies ofMountainand Hill Environment, estimate that India is planning to build 292 dams across the Himalayas.
If all of them come up, they write, “The IndianHimalayaswill have one of the highest average dam densities in the world.”
Scientific Norms? These issues are not getting the attention they deserve from the ministry. For instance, the ministry has set the minimum distance between two dams at 1 km; the minimum flow of a river at all times at 20% of its lowest seasonal flow; and it is evaluating project impact for 10 km, upstream and downstream. How did it arrive at these standards? Jayanthi Natarajan, the minister ofenvironmentand forests, did not respond to an email questionnaire on the issue. But a senior hydelEACmember, who did not want to be named, says norm-setting is a problem. “The power ministry has the Central Electricity Authority (CEA) advising it. The ministry of environment has nothing,” he says. “There are no internal regulations on norms for hydel — be it the minimum flow or the gap between projects. None of this has been defined. The EAC has just worked out some norms on its own.”
Take the 20% minimum environmental flow, which ensures there is a certain minimum water inthe riverat all times to sustain its fishes. “The previous committee had suggested a minimum flow of 10%,” he says. “We have made it the average of 20% for four lean months. But all this could change once a new committee comes in.” The 20% norm, the unidentified hydel EAC member adds, will result in at least 20 cm of water in a river. But not all fishes are bottom feeders, and it’s not clear if they can all survive in 20 cm deep water. Downstream of the Ranganadi dam, the first run of the river project to come up in Arunachal, villagers say the river no longer has dolphins.
At the same time, the committee cannot challenge the parameters prescribed by its predecessors. Says the official: “The old committee has given terms of reference (TORs) on the basis of its understanding — they think the minimum distance between one dam ending and the end point of the next dam’s reservoir should be one km. I tend to think this should be at least 4-5 km, but the TORs have already been given.”
In the absence of scientific and independent parameters, the primary source of information about a project’s environmental costs is its own EIA report. Funded by the project proponent, they inevitably seek to minimise environmental costs.
In 2012, theNature Conservation Foundation, a Mysore-based organisation run by conservation biologists, assessed the EIA report of Bhilwara Energy’s Nyamjang Chhu project. The report, prepared by two agencies, had some glaring contradictions. Both agencies listed 16 local fish species that would be affected by the project. Surprisingly, the NCF report found, only three species were common in the two lists. And there was little discussion on the downstream impact. Or, take cumulative assessments for a river or a region, which the ministry does not do. In September 2010,Jairam Ramesh, when he was heading the environment ministry, had written to the prime minister asking for a moratorium on clearances for hydel projects in Arunachal pending a cumulative assessment of downstream, environmental and biodiversity impacts. Following a hue and cry by dam supporters, the matter was dropped.
The unidentified hydel EAC member quoted earlier says the EAC cannot order a cumulative assessment; it can only suggest one to the minister. According to Neeraj Vagholikar, an activist with Pune-based NGO Kalpvriksh who has been tracking the hydel boom in the north east, there is a legal space for the EAC to ask for a cumulative impact study. “Section 9.4, form 1, of the EIA notification asks if the project has a cumulative impact due to proximity of other projects. There is a legal basis for them to commission these studies.”