6 years on, 2000-MW Subansiri still awaits integrated reservoir authority
As Subansiri dam begins wet commissioning, concerns mount over the absence of the integrated reservoir management authority
Wet commissioning of SLHEP Unit 1 (Photo: AT)
Guwahati, Oct 27: The integrated reservoir management authority for the Subansiri Lower Hydroelectric Project (SLHEP) is yet to be constituted even as the 2,000-MW project has entered the commissioning phase.
Formation of a Subansiri independent and integrated reservoir management authority before the commissioning of the dam, which had triggered legitimate concerns over adverse downstream impact, was recommended by the three-member expert committee report in 2019.
This, in fact, was the basis for resumption of work on the project – something accepted by the Assam government, Arunachal Pradesh government, Central government, and executing authority NHPC.
Unfortunately, no such reservoir management authority has been set up even after six years of the report. The committee, formed by the Union Ministry of Environment, Forest and Climate Change as per National Green Tribunal (NGT) orders in 2017, was categorical about the need to set up the reservoir authority before its commissioning.
Official sources said that instead of the mandated independent and integrated and water reservoir authority, a Subansiri Reservoir Regulation Committee (SRRC) is likely to be constituted with multiple members and representatives from the Central government, governments of Assam and Arunachal Pradesh, NHPC, etc.
The mandate of the committee is to formulate reservoir regulation SOP/guidelines for integrated operation of all present and future reservoirs in the Subansiri basin and its effective implementation in order to achieve optimum power generation and flood moderation benefits.
It will also advise releases from the reservoirs, and oversee flood forecasting mechanisms including but not limited to effective early warning system in projects located in the Subansiri basin.
In addition, it will oversee the O&M issues related to operation of reservoirs/outlet structures and also propose studies to reservoir operations as and when required.
While the reservoir regulation committee is yet to be constituted, questions have arisen why a committee should replace the proposed independent and integrated authority. The recommending panel was categorical about the nomenclature of the body as an ‘authority’.
“It is recommended to constitute a Subansiri Independent Integrated Reservoir Management Authority (SIIRMA) or Subansiri River Basin Authority (SRBA) before commissioning of Subansiri Lower Project (SLP).
“The constitution, composition, powers and functions of SIIRMA/SRBA shall be well defined to the minutest detail. By constituting SIIRMA/SRBA as well as by developing a user-friendly reservoir operation manual along with well-trained personnel and decision support system in place, the apprehension of any Panic Release can be ruled out,” the committee had mentioned in its report.
The critical importance of the proposed authority should be evident from the thrust put on its diverse aspects by the recommending panel, which it said should be defined to the minutest detail. It also asserted that such an authority was essential to negate the apprehension of ‘panic release’ of water that can trigger flash floods.
When asked, an official said that the Government of India was supposed to constitute the reservoir authority. “It has not yet been set up but it can be done before the full commissioning of the project. The Union Power Ministry is looking after the matter and we expect the required steps soon,” he said.
With the project’s Unit-1’s wet commissioning now in progress, NHPC plans to bring three additional 250 MW units online this year, injecting a total of 1,000 MW into the national grid. Once fully operational by next year (2026), the eight-unit (8×250 MW) SLHEP will stand as India’s premier hydroelectric facility.