Extreme Engineering: Rohtang tunnel project - working experience on Himalayas
Once it is open to traffic, the Rohtang Tunnel in Himlayas, India will probably be officially included in the Guinness World Records books as the longest tunnel in the world situated at an altitude of more than 3000 m above sea level.
Croatian experts on the top of the world: working experience on Himalayas
No road in the world is harmless. Ideal
weather conditions, strict speed limits,
and good visibility, can offer just a limited
help to drivers. However, some of the
roads around the world can certainly not
be ranked among the brightest points of
transport infrastructure. Moreover, some
of them are known as the most dangerous
roads in the world. The list is headed
by Indian roads, especially those built in
the Himalayas. To prevent accidents, Indian
authorities have decided to build a
tunnel through the Himalayas. The tunnel
will be of much help to villages cut off
from the rest of the world during wintertime,
when most over-ground roads remain
inoperable due to heavy snowfalls,
landslides and strong winds.
Indian roads are known as the most dangerous in the world
Marko Mrazovac is the only Croat in the international team working on the Rohtang tunnel project in India. Why is the project classified as an extreme engineering endeavour? Simply because every project considered as physically unrealisable by normal standards is no less than extreme. However, the experts and engineers somehow find the way to turn this impossible task into reality. How else could we describe successful excavation of the Rohtang Tunnel through Himalayas, during which the workers were faced, in addition to other hardships, with the lack of oxygen in the air?!
Marko Mrazovac at the Rohtang Tunnel construction site
In the spring of 2016, Mrazovac made a
new career step, moving to Strabag AG, a
large construction concern based in Austria.
Currently, he works on the Rohtang
Tunnel project in Manali, India. Mrazovac
is the Commercial Project Manager responsible
for financial and commercial
side of the project, involving finance activities,
accounting, procurement, stores,
and human resources. He is currently
managing an international multidisciplinary
team of 191 employees. Some
of the challenges and risks faced by
Mrazovac and the project team during
implementation of this megaproject are
presented in this article.
Indian road to Roof of the World
The Himalayan road, approximately 475
km in length, is located at the northernmost
end of the Indian subcontinent. It
connects the cities of Manali and Leh in
the centre of the Ladakh Province. The
road crosses top five highest passes in
the world, including Rohtang La at 3978
m, Lungalacha La at 5059 m, and Taglang
La at 5328 m above sea level. The road
is known to be a highly perilous challenge
even to the best drivers.
Mountain peaks are usually under snow
cover even in the middle of summer, and
beautiful landscape transforms each
journey into a fascinating adventure,
which unfortunately sometimes leads to
a tragic outcome. Translated into English,
the name of this mountain pass
‘’Rohtang’ means "pile of corpses", which
vividly depicts extremely dangerous
driving conditions on that road.
Once the tunnel and the new road are complete, the travel time between Manali and Keylong
will be reduced by five hours
The Rohtang Pass is located in Northeast India, at 4000 meters of altitude in the Himalayan mountains, connecting the Kullu Valley with the Lahaul and Spiti valleys. Every year, the Indian Border Road Organization uses GPS to locate the road after rockfalls and avalanches, so that it can subsequently dig it up and restore normal traffic. In the middle of the Rohtang Pass, sudden landslides and snowstorms are quite frequent and expected. However, although very dangerous and unpredictable, the Rohtang Pass attracts tourists eager to enjoy this beautiful and unforgettable mountain landscape.
Every year, from October to May, and sometimes until mid-June, the road is inoperable due to heavy snowfalls. The race to supply remote villages with food lasts from June to September when a continuous flow of trucks, buses, delivery vans, and passenger cars passes along that road. However, once the Rohtang tunnel is open to traffic, that route will be closed and the villages will finally be connected with other cities in India.
The idea of building a tunnel underneath
the Rohtang Pass dates back to 1983.
However, the project was approved by
the Indian Cabinet of Security in September
2009, and the contractor selection
process was initiated. The tunnel construction
contract was awarded to Strabag-Afcons,
a joint venture between the
India-based Afcons Infrastructure and
The Client is the Ministry of Defence of
India (i.e. its technical department Border
Roads Organization), and the project is estimated
at approximately € 235 million.
The Snowy Mountains Engineering Corporation
- SMEC International Pty. provided
design for the project. The construction
supervision was awarded to the consortium
D2 Consult ICT JV in association
with PEMS, which is formed of the Linz based
Austrian consulting company D2
and local Indian partners.
Strabag Afcons JV project team
The construction site organization
The tunnel provides ample room for two-way traffic, and is designed to cater to a maximum vehicular speed of 80 km/hr.
It is built at the foot of the Rohtang
Pass, 3060 m above sea level. It is 9 km
long and 10 m wide, with the longitudinal
slope of 0.5 %. The tunnel is one of
key structures along the future Manali –
Leh road section and will, once it is open
to traffic, reduce the distance between
Manali and Keylong by approximately 46
km, while the travel time on this section
with be reduced by as much as five hours.
The construction site organization was
not simple, and the engineers were not
fully aware of what they could expect
up in the mountains. The project team
arrived from Europe to Delhi by airplane,
and was to travel additional 600 km to
the construction site in the middle of
the Himalayas. At the first sight, it did
not seem so far as a relatively functional
motorway was used for the first 340
km. However, the real nightmare were
the remaining 260 km with the continuous
ascent along steep mountainous
roads, locally no more than three to four
m in width, full of mud and stone fragments.
It took eight long hours to complete
this seemingly short trip to their
temporary home in the middle of the
As to the site preparation work, the electricity was provided from a nearby village, because this area in India is very well electrified, so that even some smaller villages in the Himalayas benefit from electricity. However, power cuts are frequent, and the construction site is therefore equipped with diesel generators that allow construction work even when electricity is not available. Some construction machines had to be transported to the site in parts, and assembled on the construction site by site crews.
To enable proper functioning of the construction
site, appropriate site installations
and plants were assembled immediately
next to the north and south
portals of the tunnel: concrete plant,
storage shed for construction material
and equipment, plant for the production
of precast concrete elements, rock
crushing and crushed material selection
plant, and office premises. The construction
site was officially opened on 28 June
2010, by symbolic cornerstone laying.
The tunnel, with a horseshoe shaped
cross-section, has two portals (north and
south). The cross-section is composed of
three main parts: heading, benching, and
invert. The south portal excavation started
in August 2010, and the digging and blasting
work for the north portal commenced
in October 2010.
Construction site at north portal in winter (left) and summer (right)
Rohtang tunnel construction
of the tunnel were excavated by January
2012 and most of the works were being
carried out in accordance with the time
schedule. It should be noted that excavation
of the south portal progressed a
bit faster, as the north portal is situated
under the Rothang Pass, which is inoperable
in winter, and so the access to this
part of the site is then impossible .
3,5 km of the future tunnel were excavated
by June 2012 when the works were
suddenly brought to a halt. In fact, builders
were in for a big surprise in the middle
of the tunnel, in the zone called Seri
Nallah, where a ground water stream
was encountered during rock drilling
operations. That part of the mountain is
characterized by extremely poor geological
conditions and, considering that the
the planned tunnel
route, a good
composed of geotextile
had to be
installed. That is
why the planned
time was extended
but this was an
successfully overcome with the support
of the Client.
Life and work above the clouds
Although building a tunnel at an altitude
of 3000 m is a highly complex and dangerous
enterprise, this challenge represented
an even stronger motivation for
the project team, whose members gave
their best to reach the light at the end of
the tunnel, and that day finally came in
October 2017, when the tunnel excavation
work was completed.
This project is a hazardous enterprise
due to complex working conditions the
workers had to cope with in this geographically
hostile environment. Housing
units were built in the immediate vicinity
of the north and south portals to accommodate
some of the workers, while the
remaining employees were lodged in the nearby communities, from where they
were transported to the site by buses.
Up to one thousand workers were present
at the construction site during some
phases of the tunnel construction work.
A relatively frequent health problem that
affected many workers was high blood
pressure caused by lack of oxygen at
such high altitudes.
That is why some workers were unable
to take part in the work and had to leave
the project. It is interesting to note that
such health problems were not limited to
workers that came to the site from Europe,
but were also experienced by Indian
workers that came to the construction
site from low-lying areas of the country.
Another problem of the Rohtang site is its location: because of high altitude, there is no hospital nearby. Fortunately, health care was organized as part of the project, and so medical services were available to all employees on the site 24 hours a day. Educational activities and safety controls were carried out throughout the project duration, which is why no severe injuries or other accidents were reported on the site.
Despite cold mountain climate, it is unbelievable but true that many houses in nearby villages do not have any kind of insulation systems. Thus the water often freezes in pipes due to low temperatures and sometimes even the simple tasks, such as cooking or personal hygiene routines, may seem impossible.
A rather unpleasant situation occurred in
the winter of 2014 when all telecommunication
links with the rest of the world
failed in the middle of a snowstorm. The
situation remained unresolved for no
less than fourteen days, and the workers
could not do anything but wait for the
specialists to restore the communication
system. The problems were also experienced
with the delivery of fuel to the site,
and so the Team Procurement Department
had to find solutions in a number of ways.
Cold winters with heavy snow caused
problems related to construction equipment
and storage sheds. Sometimes a
winter storm dumped up to two meters
of snow in just a few hours. Therefore, in
winter months, construction aggregate
had to be stored in sheds, and construction
machinery was transported into excavated
parts of the tunnel.
On-site precast-concrete plant
In winter months,
seismic activity has been known to initiate
avalanches. In order to increase
consciousness about possible hazards
and educate workers about the situation,
an on-site expert team provides special
education for employees focusing on the
behaviour and protection rules to be observed
in case of seismic action.
The work on the tunnel is performed 24
hours a day and the working system has
been adapted to such a rapid work schedule.
Current activities include realisation of
concrete work and additional excavations,
after which fire protection, ventilation and
lighting systems, and other equipment,
will be installed. Due to specific on-site
work conditions, the Indian military is
careful in defining the project closing date.
However, once it is open to traffic, the Rohtang
Tunnel will probably be officially
included in the Guinness World Records
books as the longest tunnel in the world
situated at an altitude of more than 3000
m above sea level.
An experienced international team of experts who anticipated some potentially dangerous scenarios, and prevented financial losses and site accidents, was the key factor for successful implementation of the Rohtang Tunnel project. In addition to the experience and good quality communications, managing cultural diversity of the multidisciplinary team was also very important. The Strabag Afcons Joint Venture has managed to reach its first common goal – tunnel excavation - and is now looking with optimism to the final completion of the tunnel and the works.
Considering all perils
– such as human health hazards - that
have been successfully overcome by the
workers on the Himalayas, it can finally
be concluded that this project, a veritable
endeavour that exceeds current limits
of engineering, can simply be described
with three words: Impossible is nothing.
Full article is published in research/professional journal Gradjevinar:
Authors: Anđela Bogdan, Marko Mrazovac, Josip Sertić
Photo Credit: Strabag Afcons JV