The strong winds put the aerial reconnaissance at risk 

Tshering Palden

The weeklong aerial feasibility survey of the 10.5km proposed tunnel between Thimphu and Wangduephodrang that began on December 13 was suspended after the first few trials.

Instead, the Department of Geology and Mines officials said it would be complete before the second week of February.

The department’s seismology and geophysics division head, Dow- chu Drukpa, said, after attempting for two days, they could not conduct the survey.

SkyTEM, a Danish consultancy firm specialising in geophysics surveys, is conducting the survey using a helicopter and the latest technology. The survey is one of the joint projects between the Norwegian Geo-technical Institute (NGI), Norway, and the geology and mines department.

NGI’s regional manager (Asia) Dr Rajinder Kumar Bhasin, in an email, said the survey was suspended because of high winds in the area.

“The pilot didn’t feel comfortable in flying with the antennae just above the tree tops under the existing conditions,” he said.

He said, therefore, Sky-TEM was now in the process of identifying a pilot, who has experience in flying with this equipment.

In addition, because of the effect of high altitudes, they were also looking for an even more powerful helicopter than the Eurocop- ter, which they used last time.

“I think the effect of the above delay is that the delivery time for the data will be extended, but with- out any cost escalation,” he said.

Dowchu Drukpa said the contract between Norwegian institute and SkyTEM provided a time extension for such delays.

“As per the contract document between NGI and SkyTEM, suspension of work on grounds of safety that the pilot recommended should extend data delivery times,” he said.

Dowchu Drukpa said his division submitted wind data of the past few seasons from the hydromet division to NGI officials for analysis.

“It came in during a windy season, so they’re now analysing the data and deciding on the best time to come in, but it would be sometime before mid-February,” Dowchu Drukpa said.

Should it delay further, the wind current would only worsen. Norwegian agency for development funded the project worth USD 1.2M.

On completion of the aerial survey, drilling work would begin, on which they would submit a report to the government.

Geology and mines department, in the first phase, conducted the geological and preliminary studies, which included the “walk on survey” of the proposed 10.5km tunnel road between the two dzongkhags, which begins from Yoesepang in Thimphu until Nabisa in Wangduephodrang.

If the tunnel comes through, the proposed two-lane road would reduce the two-and-a-half-hour travel to less than half an hour.