A plan to protect the formation of the roads would be discussed this winter
Highway: A multi-pronged solution is planned this winter to address the perennial roadblocks at Reutala between Trongsa and Zhemgang and Box Cutting in Gelephu, according to the works and human settlement minister (MoWHS), Dorji Choden who visited the sites on September 12 and 13.
“I purposely came to visit Reutala and Box Cutting because these are two unstable and landslides prone road points causing roadblocks perennially between Trongsa and Gelephu,” lyonpo Dorji Choden said.
The ministry would sit with experts from the department of geology and mines, which is currently conducting a study at Box Cutting to plan on the mitigation and structural reinforcements such as construction of check dams, retaining walls and water management.
“Plans are not just on how to deal with monsoon clearances but bigger sustainable project needs to be initiated at Reutala and Box Cutting,” lyonpo said, adding separate bigger project needs to be initiated.
Reutala located around 84 kilometers from Trongsa has persistently reported roadblocks for over seven months. Box Cutting, which also falls on the Trongsa-Gelephu highway, has also reported perpetual roadblocks yearly.
Annually, the department of roads (DoR) spends Nu 4.7 million (M) on an average to keep the road in Reutala clear of debris and ensure that the road is open to traffic during those seven months.
“This year, just to clear the blockades in July, an expense of Nu 1M was incurred,” Koshala’s sub-division assistant engineer, Letho Dorji said.
Clearing the debris and constructing protection walls at Box Cutting costs DoR Nu 6.5M annually. However, the spending has neither been able to stabilise Reutala or Box Cutting because the entire hillock is stationed in unstable geological condition and prone to massive slides during monsoons.
The minister said that although the duration of roadblocks at Reutala and Box Cutting has been reduced over the years with availability of adequate machines and manpower, the ministry is now studying to come up with a more robust and sustainable solution.
“Therefore, in winter engineers and experts are going to sit together to discuss and plan on what needs to be done,” lyonpo Dorji Choden said.
For instance, structural measures like construction of walls below the road in Box Cutting has proved effective in at least protecting the formation of the road even though the hillock has been sliding from its weak and instable geological condition.
“Now the ministry’s objective would be to protect the formation of the road so that it isn’t washed away by the slides,” the minister said.
In Box Cutting, as proposed by Sarpang dzongkhag engineers, priority would now be to protect the formation of the road with construction of walls intermittently to reinforce the existing barriers. Letho Dorji said even for Reutala, the only possible solution is to protect the existing road with boulder walls from the base and clearing debris from above.
The ministry decided to stick with the existing road after experts from Japan ruled out the options of tunneling or realignment for Reutala and Box Cutting respectively. While tunneling proved too costly for diverting just less than 150 meters long stretch of road in Reutala, realignment of Box Cutting hasn’t received positive response either because of an entire area reeling under poor geology.
“The cost of diverting the road through tunnel is likely to cost the department about Nu 650M per kilometer,” DoR’s geo-technical engineer, Tempa Thinley said, adding that tunneling wouldn’t shorten the distance either.
Lyonpo said the slides would continue even in future but DoR would ensure the formation of the road is protected.
“But with continuity of slides even Reutala and Box Cutting could stabilise on its own like Tintalay between Wangdue -Tsirang highway,” lyonpo Dorji Choden said. “Reutala and Box Cutting would be an engineering challenge but it would need to be dealt with feasible long-term solution that’s both technically and financially sustainable.”
Tempa Wangdi, Gelephu