Are dam site blasts cracking the dzongs

Test: The glass would
 break if the cracks were
 indeed caused by the blasting

Some Indian experts were hired to conduct a study, the result of which is awaited

Mandgechu Project: Recent artificial tremors and subsequent cracks on some of the landmarks of Trongsa, residents and authorities of the dzongkhag attribute to activities being carried out at the Mangdechu hydropower construction site.

Authorities have reported of extension on existing cracks on the walls of Trongsa dzong that overlooks the gorge of the Mangde river, and fresh cracks appearing on the walls of the renovated Ta-dzong (watchtower) above the dzong.

Trongsa residents said, ever since work on the Mangdechu project began, heavy sounds and echoes of explosion from the dam construction site, a few kilometers below the dzong, have been regular.

Over the months, the loud explosions began showing their impact, dzongkhag authorities said, on the landmarks of the dzongkhag.

Ta-dzong’s officiating curator Loday said the three-storey block of the watchtower, which serves as meditation centre and security room, have developed new cracks since a few months ago.

He said, a few days ago, some Indian experts that Jaypee association hired to conduct studies on the relationship between explosions at the dam site and damage to the dzongs, said there was none.

“They said the cracks weren't new and that they weren't caused by the blasting at the dam site,” he said, insisting there were no crack on the walls of the structure before. “These cracks are a few meters long.”

Others staying inside the Ta-dzong said, whenever there was blasting at the dam site, they felt vibrations and heard their windowpanes quivering.

Loday also said, the experts told him the vibrations they experienced was not from the blasting per se, but the echo the explosion let out.

“We aren't really blaming the project, but there’s a need for a thorough investigation,” he said. “For the sake of saving and preserving the age-old museum from damage, it’d be better if local experts are invited to conduct studies.”

He said they would be in better position to understand the situation.

Tremors from the explosions have also caused additional cracks on the walls of the Trongsa dzong.

Dzongkhag officials from the engineering section, who inspected the damage, said, although no new or major cracks have been formed on the walls of the dzong, little hairline cracks have been seen extending along the old cracks.

One of dzongkhag’s junior engineers said, according to the experts, that Jaypee hired from National Institute of Rock and Mechanic (NIRM) India, who following some survey, had concluded that cracks were not new and not caused by the blasting.

“They said it was possible the blasting could cause damages to structures, if it was happening within a 300-meter diameter distance,” they said. “The dzong, they said, was 1,600m away from the blast site.”

Apart from the two dzongs, the proprietor of the View Point guesthouse, opposite Trongsa dzong, said gaps had begun appearing around the edges of the window frames, fixed on the concrete walls of her staff quarters.

Proprietor Karma Tsheltrim said she even lodged a written complaint to Mandgechu hydropower project authority.

To find out if cracks on the walls of the two dzongs were really caused by the blasting occurring at intervals at the dam site, the experts have glued rectangular glass slabs, the size of a data card, on some of the cracked walls of the two dzongs.

“The glass is supposed to determine if the cracks were indeed caused by the blasting,” the junior engineer said. “It’s supposed to break in the event of another blast.”

An engineer with the project said the issue of cracks on the walls of the dzong was reported before the project began.

A site engineer at the dam construction said at least three to four blasts were being carried out in a day, although officials claimed not to know how much blasting was done so far since the project began.

“All blasting is done in a way that ensures minimal affect in the area,” he said. “For less damage and less vibration, a detonator was used for blasting.”

Jaypee official were unable to comment on the issue, saying the two scientists they hired were studying the case.

“Such problems can’t be solved through discussion but through scientific methods,” he said, adding the actual causes of the cracks on the dzongs would be known only after they received the survey data from the experts, who are leaving the country in a few days.

The findings of their report are expected to take about a month.

Some locals, however, expressed skepticism if the study is being conducted without any slant to favour the company that hired the experts, and if the actual facts and real results will be shared.

Save for the Trongsa dzong, the Ta-dzong and the guesthouse, no other complaints have been reported so far.