The ongoing highway-widening project will even open fresh wounds where there could be more “shooting boulders” and landslides. As an engineer in my previous life, I thought, “Could it possible that there is absolutely no solution?” Some random thoughts followed including a suggestion a chillip engineer made to a friend of mine who then made it to me over some coffee – half tunnel!
Studying the area for few minutes and imagining a half-tunnel through, I found it does make sense. Half-tunnels are like ordinary tunnels but with wall on the hill side and no wall on the slope side. If the earth cover over the tunnel is thick, columns are built on the empty side to avoid the roof from collapsing. I have seen such tunnels in the Italian Alps where avalanche are common problem.
Half-tunnels have several advantages. They involve less cost and time to build than the normal full-tunnels. And unlike the full-tunnel that requires stringent safety considerations against fire and tunnel accidents, the half-tunnel having one side open does not present such serious safety issues. Hence, even the tunnel option from Geduchu to Gonglakha, which someone suggested, needs to be to be looked into from this safety perspective.Once built the half tunnels could present a long-term solution. Any slides or boulders falling off will shoot straight for the valley without falling on the road (see above diagram). It could finally provide the solution to the monsoon nightmare. Therefore some serious studies could be initiated to see the feasibility. True there could be huge short-term construction cost. But these should weighed against the long-term benefits and how much this country is losing, as a whole, in terms of time, resources and manpower every year. With all the talks about climatic change, the need for a long-term solution is even greater.