What ails the national highway?

The lifeline to Kashmir valley, the Jammu Srinagar National Highway, has remained blocked for traffic for a large part of this year. Even when it is intermittently opened to traffic it is invariably open to only one way traffic. The local media and the various trader associations have been regularly highlighting this issue since it is very adversely impacting the already tattered economy of the state, particularly the Kashmir province. Scores of meetings have been held by different government agencies at various levels to review the situation but there has been no improvement on ground. Recently the Chaiman of National Highway Authority of India also visited the Valley, to take stock of the situation.

Other than providing assurances that the issues will get resolved none of these meetings have come up with any concrete action plan. Interestingly, a press release after one of these high level meeting seemed to suggest it to be an issue caused by wrong parking of vehicles and by debris being stacked along the highway. For now the problem seems to have been abated but it will crop up again once the rainy season starts. 

We are all aware that prior to the start of its widening the highway was generally stable. We have had days when it would get blocked for various reasons, including landslides, but these blockages were occasional and cleared fairly quickly.   

While the widening of the major length of the highway has generally not been an issue, the length between Ramban (Digdol) to Banihal has caused serious disruptions to traffic because of the frequent landslides along this stretch of the highway. It seems that the design for widening of this particular stretch of the highway has not been properly conceived. Clearly the geological formation in this stretch of the highway is different to rest of the highway and required a more detailed geotechnical survey investigation and study before it was designed.

A hill road anywhere poses severe challenges first to the design engineer and then to the construction engineer. Amongst others, these challenges are related to the grade, sight distances, drainage and to stability of the road including the stability of the slopes on either side. And these challenges get exacerbated when you are widening a highway in a geologically unstable area of a young mountain range like the Himalayas and at the same time are trying to keep the highway open to traffic.

Stability of hill slopes is an important function of the geology of the area and plays crucial part in planning and design of hill roads. It is of paramount importance to ensure stability of the formation and to prevent any slides from the hill side. Where required, these slopes need to be specially treated to ensure their stability.

The stretch of the highway under discussion is very unstable and consists of loose and fragmented formations. Cutting into such a hill side to widen the road has disturbed the slopes, made them steeper and/or longer, thereby destabilizing the hillside and hence the slides. And vibrations caused by blasting and frequent rains in the area has only  worsened the situation.

In such situation there are different types of solutions and treatments available to prevent slides. One of them is to extend the excavation to upper reaches of the hillside to obtain a milder slope there and then undertake treatment of the slope. And in this instance this is where we seem to have a problem – the upper slopes have neither been made milder nor treated nor stabilised. 

The contractor appointed for the widening of the highway has been given a certain width / corridor (called Right of Way – RoW) to widen and construct the road and to treat the hillside slopes within this corridor. The loose geological formation of the slopes obtaining at the site requires the contractor to go well beyond and above this corridor demarcation for excavation (to make the slopes milder) and for treatment to stabilize these slopes. It seems he is not doing so as the area falls outside the RoW, the boundary limits of his contract, hence out of his scope of work and thus he will not be paid for it.

In absence of this additional excavation and treatment of the slopes above the RoW line, the loose material there slips and causes slides which block the highway. The executing agency needs to look into this issue and issue necessary instructions as otherwise if they continue the way they are currently going, i.e. clearing the slides as they occur, it will be decades before the slopes are mild enough to stabilize on their own.  

People who frequented the highway in the 70’s and 80’s might recall that we had a similar situation at the Nashri slide near Batote. This famous slide continued to be a travelers’ nightmare for decades. Slope stabilization measures were not common then and instead millions of cubic metres of slides were removed over decades till virtually the hill slope flattened out. But given that today daily thousands of vehicles use the highway we cannot wait for decades for these slopes to be mild enough to stabilize, like Nashri slide.

As regard slope treatment, since improper drainage also induces slides, the slopes need to be treated by way of shotcreting to prevent water ingress and drain pipes installed to drain out water from within the hillside. The rock mass on the hill side will need stitching; installation of bolts and anchors into the hill side to stitch together the fragmented rock mass. And wherever appropriate some stretches might require grouting to consolidate whatever rock mass there is.    

The implementing agency needs to move quickly on this to get the necessary works executed since Kashmir province cannot afford for long this kind of disruption to the traffic on the highway. It is daily costing the business in Kashmir, and hence the people, crores of rupees which is much more than what it would take the agency to provide a proper engineered solution to the problem.