While the fate of the dam construction of the Punatsangchhu Hydroelectric Project Authority-I (PHPA-I) remains uncertain with it missing its latest deadline in 2019 and a third party review of the feasibility of the right bank construction currently underway, there are no plans to abandon the project, according to Managing Director of Druk Green Power Corporation (DGPC), Dasho Chhewang Rinzin.
Dasho Chhewang Rinzin said the project will not be abandoned. “One or the other solution should soon emerge to complete the project for the benefit of both the people of India and Bhutan. Everyone is working together with the intent on finding a way forward to successfully complete the project,” he said.
Third party reviews are currently undertaken by some internationally recognized consultancy groups to ascertain whether it would be technically feasible to build the dam at the present site.
“The design and engineering for the dam and the proposed stabilization measures need to adequately ensure the long term stability of the dam. While there might be some feasible solutions, the question is also the need to consider the associated costs,” said Dasho Chhewang Rinzin.
The third party reviews of the present dam site should be available by January 2021 and if the present dam site is found to be not feasible, the Detailed Project Report (DPR) for the barrage/weir option would also be available by mid-2021 for the two governments to consider.
In an event the dam cannot be constructed at the present site, apart from the third party reviews of the dam, investigations are also being undertaken to prepare a DPR for a barrage or a weir option upstream of the present dam site.
According to the initial findings from the DPR investigations, a barrage or a weir is feasible upstream of the present dam site with a connecting headrace tunnel. This would ensure completed components of the Punatsangchhu works can be used.
The Managing Director of PHPA-I, Naveen Chander Bansal said, “As such, at the stage, it is premature to conclude that dam cannot be constructed at the existing location.”
He said that the project will assess the impact and cost escalation after they receive the report of the third party review. According to DGPC, the governments of Bhutan and India are exploring different options available to complete the project.
Except for the dam, the other major components of the project starting with the intake structures to the headrace tunnel and the powerhouse have already been constructed. The installation and erection of the electro-mechanical equipment in the powerhouse are being continued and should be completed by the end of 2021.
“The problem is only with the construction of the dam as the dam abuts with a right bank that is creeping downhill into the riverbed that is manifested in the July 2013 major landslide and the subsequent land slips within the overall 2013 landslide area,” said the DGPC Managing Director
Many expert groups have considered the landslides and the landslips but the proposed stabilization measures have so far failed to arrest the creepage of the hill slope into the riverbed. Since a definitive proposal for moving ahead with the dam construction was not emerging, the two governments have agreed on a third party review of the dam site as suggested by the Bhutanese government.
Meanwhile, Dasho Chhewang Rinzin said that it is not expected that any project should fail. The two governments are working very hard towards making the Punatsangchhu project successful.
The PHPA-I, a 1,200MW project, is the largest hydropower construction project in the country, being built with a budget of Nu 93.76bn, of which a total of Nu 79.30bn has already been spent so far. The initial project cost was Nu 35bn.
The construction of PHPA-I, which started back in November 11, 2008, was initially planned for completion in December 2016. However after several failed attempts to stabilize geological problems including the slide prone area at the right bank of the dam, it missed the project completion date in November 2019 which has now been deferred to 2025.
Since the slide of the entire slope of the right bank in 2013 of the PHPA-1 due to geological issues, the construction of the project has experienced delays and cost escalation, becoming the subject of national debate and criticism. Two more major slides have occurred at the site, one in August 2016 and another in January 2019. As of July this year, PHPA-I achieved over 85% of the overall construction works. PHPA-I is expected to generate 1,095MW of electricity.
Chencho Dema from Thimphu