The dam is now expected to be completed only by the end of 2018

Hydropower: Completion of Punatsangchhu Hydropower Project Authority (PHPA) II will be further delayed by six months.

This is as per the authority’s proposed solution to address a problem that occurred in the downstream surge chamber on March 3. Six workers were killed when loose soil and muck collapsed on them on that date.

The 1,020 megawatt hydropower project was scheduled to be completed by December 2017.

However, following adverse geological problems last year,  completion was rescheduled to June 2018. Now, the completion is postponed to  December 2018.

Prime Minister Tshering Tobgay, who visited both project sites on September 11, said that while the project management’s proposal looks fine to him, they will still need to sit with experts, finalise the proposal, and get all the required approvals from all authorities concerned.

Apart from the rectification works at the surge chamber, PHPA-II is also faced with a geological problem. There is a shear zone or a crack on an area that was discovered during construction, which has also caused some delays, said Lyonchoen.

Dam construction of PHPA-II was also delayed following the recent monsoon which caused the Punatsangchhu to rise and spill over the cofferdam and enter the dam construction site. The water and muck had to be pumped out.

Lyonchoen said with regard to PHPA-I, except for the dam construction, other works are going smoothly. During his visit to the powerhouse, he said he saw people installing the generators, high-pressure shafts and several other important equipment, he said.

“The scale of work and technologies involved are impressive,” he said. “I am very content to see many Bhutanese involved at various levels at the hydropower project construction.”

Like PHPA-II, the PHPA-I dam is also faced with a geological problem. While excavating for the dam, a weak portion caused by a shear was detected on the right bank. Following responsive measures, the shear continued and it became larger than anticipated.  “Recently, we discovered that it is spreading further downstream than anticipated,” he said. However, the rectification work is going on full swing, he added.

PHPA-I was initially set to be completed by November 2016, however, following several delays caused by geological surprises, it is now scheduled to be completed by 2019 end.

Meanwhile, Lyonchoen said that despite being sufficiently briefed on the progress of the hydropower projects, he tries to frequently visit the sites to understand what is going on and also to lift the spirits of the people working at the projects.

Dawa Gyelmo | Wangdue