Report also recommends it is better to do a few mega projects than many small and medium project to lessen environmental and social impact
The much anticipated Hydropower Committee report has not only recommended slowing down hydro development and going for lesser but more viable projects (see main story), but it has also delved on lessening the environmental impact of hydro projects.
The report says that in the past, economic interests may have tended to overshadow environmental concerns with environmental clearances being provided on priority basis to facilitate development of hydro projects.
It says since most of the projects were run-of-river schemes,the impact on the environment has so far been limited.
The baseline scenario of hydropower development, according to the report, shows that Bhutan will be able to meet its economic goals without having to really accelerate hydropower development as envisioned earlier.
“Given this more comfortable scenario, it may now be timely to seriously consider how the larger environmental concerns may be addressed, while simultaneously developing Bhutan’s hydropower potential,” says the report.
It says that while Bhutan will have to continue developing hydropower as this is the largest natural resource it possesses, the challenge will be as to how to pursue hydropower development while limiting the impact on the environment, and take into consideration inter-generational choices.
The report says Bhutan has several river basins suitable for hydropower development and since there are environmental issues regarding damming of river systems, the report explored the possibilities of keeping some river basins free of hydropower development till 2030.
It says while hydropower development has taken place in the Wangchu basin, the Punatsangchu basin and the Mangdechu, Kurichu, and Gongrichu sub basins of the Drangmechubasin, a lot of potential still remains to be developed in these river basins and sub basins.
The total remaining balance hydropower potential in basins and sub basins that have already been developed is 12,376 MW. This is about 68% of the balance hydropower potential that could be developed says the report.
At present, the Amochu basin and the Chamkarchu sub basin of the larger Manas basin remain undeveloped.
The Chamkarchu basin has a potential of 3,299 MW and the Amochu basin has a potential of 1,975 MW, which accounts for about 28% of the balance undeveloped potential.
The report says that to address environmental concerns, it may be prudent to continue development in basins where hydropower projects already exist or where new hydropower projects are already being built instead of starting projects on all the river basins.
It says there seems to be an opportunity to protect some of the basins from hydro development for the next 10-20 years.
Later on, if the difference in financial viability is substantial between projects in the developed basins and undeveloped basins, considerations can be made to start some projects in the remaining undeveloped basins.
“In the meantime, a better understanding of the impact of damming river systems could also be expected to emerge,” says the report.
From the list of projects that are ready for implementation and in basins that already have existing hydro projects, there is the Sunkosh (2,585 MW) project in the Punatsangchu basin, and the Bunakha (180) and Wangchu (570 MW) projects in the Wangchu basin, and the Dorjilung (1,125 MW) and Kuri Gongri (2,640 MW) in the Drangmechu basin.
Therefore, the report says, a total of 7,100 MW can be developed before even considering the opening up of the other undeveloped river basins and sub basins, which would enable the economic goals to be largely achieved while keeping some basins untouched for the time being.
Such an approach would ensure that the Amochu and the Chamkarchu basins could be kept undeveloped for the next decade or two.
Once the potential in the other basins become unviable for development, a choice could be made as to whether the Amochu or the Chamkarchu should next be opened for hydro development. The report says it will provide future generations a choice with regard to deciding which river basin(s) to keep undeveloped.
In the meantime, the report recommended that a long-term study be conducted to see the real impact of dams on river eco-systems.
The report, however, noted that the Chamkarchu I is one of the four JV projects and that work on the preparation of the DPR for the 590 MW Chamkarchu II has been initiated through World Bank financing
Better a couple of mega projects than many small projects
The report says that as local communities benefit from better economic prospects, access to health and education services, greater employment opportunities, and greater overall socio-economic development for the Bhutanese at large, local communities have been highly supportive of hydropower projects.
It says through careful implementation of the social and environmental safeguards, the issue of “Not in My Backyard” (NIMBY) has not perpetuated in Bhutan as yet, as has been the bitter experience in India and elsewhere. It says the support though may dissipate in the future with lobbies against dams reaching even the villages. Over time, while it may not be difficult to get clearances for implementation of smaller projects, it will become more and more difficult to get clearances for constructing mega projects.
Therefore, the report says that careful consideration has to be made on whether to proliferate small, medium and large hydropower projects throughout the country or prioritize a few mega projects that could actually generate sufficient revenues and stimulate socio-economic development.
It says as the emerging market trends show the requirement of balancing power for the grid as well the opportunities for higher revenues from ancillary services, it might be better for Bhutan to consider one or two mega reservoir schemes in place of a large number of smaller projects.
It says that apart from the multipurpose use of reservoirs, the social and environmental impact of the one to two reservoir schemes could be far less than the aggregate impact of a multiple number of smaller projects. For the markets in India and the region, large reservoir projects would be strategically preferable in terms of both energy and water security.