Kashmir Rail Link Project: New revelations of landslides and structural failures

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The failures are so serious that these could also indefinitely delay construction of the Kashmir Rail Link

Where is the project headed?

Alok Kumar Verma, IRSE (Retd.)

Till about a fortnight ago, little was known about the landslides and ground failures at the 8.6 km long Tunnel T-74 and 3 bridges (Bridge Nos. 40, 41 and 42) where according to Railway construction had either been completed or was nearing completion.

This comes within months after the revelations of massive landslides at Sumber and Sangaldan.

The information that I have gathered about these failures provides further evidence of Railway Board’s debacle on the project.

About 2 months ago, the roof of tunnel T-74 collapsed and a huge cavity formed. About 50 houses in the village Tatnihal, which is situated on the mountain slope right above the tunnel, suffered structural damages.

This collapse occurred about 2 months ago. But, I came to know about it just about 2 weeks ago when I found a link to a YouTube video clip which was posted by a local TV news channel.

The video clip was taken down soon after I mentioned this failure on a forum of IRSE officers on WhatsApp. This forum has retired and serving senior Indian Railway engineers some of whom have dealt with this project.

This is not the first time that such a thing has happened. Four video clips of construction work at Chenab Bridge approach, the landslide at Sumber station site, and two tunnel adits were removed within an hour of my comments on the same forum about the serious stability issues that were apparent from these videos despite costly slope stablization.

Link to the post which I had made then is given at the end of this post. I will cover the roof collapse at T-74 in more details, but before that let us take a look at the aforesaid bridges.

The case of the failure at these three bridges (Bridge No. 40, 41 and 42) is quiet curious. In progress reports, Northern Railway shows the bridges as completed. But, the fact is that the bridges were left incomplete by the previous contractor who abandoned the work about 14 years ago in 2007.

Since then, the landslides seem to have damaged the incomplete structure of the bridges. After 12 years, in March-April 2019 Konkan Railway floated a tender for a contract for construction of the balance work of these bridges. Cost was estimated as INR 43.44 crore. It is not known whether any contract was awarded.

These are bridges of the type with box culvert at the bottom of the khad/ravine and 20 to 50 meter very-high embankment above to carry the railway line. Bridge No. 40 is near the proposed Reasi station, and Bridge Nos 41 and 42 are on Katra-end approach of the much touted Chenab Bridge.

You can see graphical presentation of the sites of these bridges in two sketches given in this post. The first sketch shows Bridge No. 40 along with Bridge No. 38 and 39. The second stretch shows Bridge Nos. 41 and 42 along with Bridge No. 43 and the mega arch bridge over Chenab. I found these sketches on the internet from reliable sources.

I think the basic conceptualization and design of these bridges is flawed because of the geological and geotechnical features of the steep slopes at the bridge sites, and this fresh attempt to build these bridges, almost 14 years after construction initially began, may also fail.

The question that needs to be answered by the railway is why these bridges are being shown as completed in the progress reports though much of the bridge work is still to be done? and why there was no construction activity for more than 12 years?

At Sangaldan and Sumber also construction was stalled for long duration of 14 years and 4 years respectively after landslides damaged the structures.

A rough estimate shows that about INR 500 crore will be spent on remedial and restoration measures at the above mentioned 6 locations (Tunnel T-74, Bridge Nos 40, 41 and 42, and the cuttings and bridges at Sangaldan and Sumber).

The failures are so serious that these could also indefinitely delay construction of the Kashmir Rail Link. Yet, little information is in public domain through news channels and social media, and as it has repeatedly happened in the last few months little information that is available is promptly removed.

On the other hand news channels and social media are flooded with news of every small development at the site of erection of the mega arch ring at Chenab and the cable-stayed bridge at Anji, and, lately, about Bridge No. 39 and 43.

For the bridge over Chenab, all the talk is of erection of the arch and how it would become the world’s tallest railway bridge, but nothing about the issues of stability of the foundations and vulnerability for a catastrophic collapse of the bridge that could render closure of the line for years.

The Sreedharan Committee had said in 2015, that the alignment should be changed. This is what it said about risk of closure of line for years on account of the mega arch bridge at Chenab:

“Because of the narrow width of the gorge at the site and abrupt drop in ground levels on both upstream and downstream, there is high risk of long closure of the Railway, in the event of damage to the bridge by a large landslide or a localized slope failure. The bridge being close to LOC, is highly vulnerable as an enemy target. In this militant effected sensitive area, a bridge of this magnitude can also be an easy target. If this bridge is damaged, its restoration will take 5 to 6 years minimum. As a result, the link to Kashmir Valley may remain disrupted for years together.”

The roof collapse at Tunnel No. 74 near Banihal:

The roof of the tunnel has collapsed in a substantial length and a huge cavity has formed at this 8. 6 km long tunnel. Excavation of the tunnel was completed on 03.10.2020, using the NATM method. The cavity is so huge that about 50 houses of the village on the mountain slope above the tunnel have also been damaged. Because the video clip of the news of this collapse is long, I am giving here four most relevant portions of the original clip, a copy of which I have.

Only a detailed investigation of the rock mass above the tunnel will show the extent of damage and cost and time of restoration. My rough estimate is that this failure is on scale of the landslide failures at Sangaldan and Sumber. My assessment is that restoration of this tunnel could take months if not years.

I had inspected this stretch in 2008, and in my report to Railway Board I had mentioned this as one of the worst stretches of the alignment. Construction on the Katra-Banihal Rail Link was suspended for about a year in 2008-09 for a thorough review of the alignment, but the review was scuttled. Below you can seen a slide from my presentation to the Ravindra Committee in Jan’2009. Link to my post about scuttling of the review is also given below.

What happened in the scuttled review is that instead of changing the whole alignment about three-fourth of the alignment was changed in bits and pieces. The alignment in the Arpinchla-Banihal stretch was changed, and the present Tunnel No. 74 was formed by merging several smaller tunnels and some bridges and cuttings.

Because ruling gradient was limited to 1 in 80 (I proposed 1 in 44 gradient that would make the alignment much shorter and straighter with just 8 tunnels and 7 bridges.), Tunnel T-74 remains in highly crushed rock strata at a very shallow depth below the slope surface. This bad alignment seems to be the reason for this incidence of roof collapse.

Where is the project headed?

Because the alignment is deeply flawed with very high exposure to the geohazards, I think we could soon see more such revelations of tunnels, bridges and cuttings which Railway claims have been completed or are nearing completion but which have actually begun to fail.

Originally targeted for completion in August 2007, the project has seen many revised target dates for completion of construction on the 111 km long  Katra-Banihal section which now forms the missing link of the rail line to Srinagar and onwards to the border town of Baramulla.

The Government of India has now asked Board to complete construction by December 2022. The Hon’ble Minister for Railways is regularly monitoring progress in meetings with Board and Northern Railway. But, as I have said earlier also (Please see post in the link below) completion is unlikely before 2030, while cost of construction will balloon. Yet, the line so completed will suffer from high risk to safety of passengers and short and long term stability of the line.

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