INDIAN PLUMBING TODAY
COVER STORY
Revitalization
of the
Water Channels
& Fountains
for the Gardens of
Humayun’s
Tomb
Mahender Kumar Gupta
History of Humayun’s Tomb
Emperor Humayun sat on the throne at the
age of 22 succeeding his father Babur, the
founder of the Mughal Empire in India.
However, Humayun met an untimely death
after a tragic fall from the steps of his library
in the Purana Kila complex in Delhi. He was
48 then. After nine years of his death, his
tomb was built under the supervision of
Hamida Begum, his widow, during the reign
of their son Akbar. The site for the tomb
was chosen on the banks of Yamuna river
because it was Humayun’s wish to bury him
near his spiritual Guru Hazrat Nizammudin.
The construction of tomb was completed in
1572 A.D. at a cost of 15 lakh rupees (1.5
million) at the time. It was designed by the
architect Mirak Mirza Ghiyas, a Persian
from Herat, now in Afghanistan. Influenced
by Persian architecture, the tomb stands
on a platform of 120 sq. m. and reaches a
height of 47 m. Built of rubble masonry,
the structure is the finest example of the
use of both red sandstone and white marble
on a large scale.
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Today, the tomb of the second Mughal Emperor is
amongst the twenty three World Heritage Sites in India.
The chahar-bagh, or four-part paradise garden, is the
earliest existing example of the Mughal garden tomb.
The tomb and gardens are considered one of the
precursor typologies of the Taj Mahal.
levels, etc. as well as different aspects of the site relating
to revitalization of the gardens through the water
channel system. Various discussions and interactions
with the site and the other specialists involved,
highlighted these requirements as well as constraints
to be kept in mind to facilitate any kind of proposal.
The gardens are laid out in a classical chahar-bagh
design symbolically patterned to represent the Islamic
notions of a paradise. Gardens are divided into quarters
by raised causeways. The quadrants are divided, in turn,
into eight plots, each with walkways. At the
intersection of these walkways are octagonal or
rectangular pools.
Two major scopes were defined as integral to the
revitalization of this site:
(a) Revival of water channel network system
(b) Revival of water fountains
Revival of Water Channel Network System
To be able to consider a scheme to revive water channel
network system of this complex, which is almost 450
years old, was a daunting task, as it involved various
layers of historical studies and assumptions, which
included a study of the existing conditions with not
very significant background of the original work. It also
considered the fact that many changes and alterations
may have been made to the original scheme in the
subsequent years. Some techniques/methods, which
were followed to understand these changes, were:
•
•
•
•
Gardens & Fountain
The main monument of Humayun’s tomb is surrounded
by a network of channels, which has water flowing
through them to create an oasis of tranquility. Though
it is not certain, whether water used to flow through
the system or re-circulate, the proximity of the Yamuna
river in the past, and the presence of historical wells
and remains of aqueduct-like structures indicate that
water used to flow through the system entirely by
natural means, through fountains and channels.
Existing Water Channel Network
•
The main monument of Humayun’s tomb is
surrounded by a network of channels, which pass
through the gardens, forming three rings around the
tomb, namely inner, central and outer rings.
Historically, water used to flow through these
channels, presumably at relatively slow speed. The
approximate average dimensions of channels were
found to be of a width of approximately 20-25 cm
and a depth which varied from 5-30 cm.
•
At the time of the initial study, entire network of
water channels was defunct. Many portions of the
channels were filled up with accumulated silt/debris.
•
Based on the site survey reports, the top and bottom
levels of the channels were studied thoroughly. Many
levels were irregular, presumably due to settling/
filling up, as well as previous alterations, which
could have occurred during the past centuries. Due
to this, the slopes were also irregular at most
locations and followed an almost illogical pattern.
Objective of the Project
Restoration of Humayun’s tomb was started by the Aga
Khan Trust for Culture (AKTC), Geneva in collaboration
with Archaeological Survey of India (ASI) in 2000. Under
the project, major restoration and environmental
development works were taken up for this landmark
site.
The objective of the project was to revitalize the gardens,
pathways, fountains and water channels of the chaharbagh, or four -part paradise garden surrounding
Humayun’s tomb in New Delhi. To ensure that the site
was rehabilitated according to the original plans of the
builders, site works encompassed a variety of
disciplines, including archaeology, conservation science
and hydraulic engineering.
M/s MKG Consultants became associated with the Aga
Khan Trust with a view to understand the hydraulics
of the existing system of water channels, its condition,
NOVEMBER 2011
Sizing/leveling of channels and flow determination
Preparing detailed proposal of channel network
Collation of data regarding source development/
treatment/pumping
Systemic understandings of distribution/collection/
re-use
Approach for Planning
•
Historically water flowed in from the centre of the
northern side and a few meters south from the
western side. After a detailed study of drawings and
the site regarding the levels, slopes and related
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aspects, it was decided to propose in principle to
retain this direction of flow, as maximum as possible,
to ensure that minimum disturbance/nuisance is
created within the landscaped area of the site.
Considering that this project was a part of a World
Heritage Monument and the significant
archaeological elements and historical value of the
site, it was neither desirable nor recommended to
undertake any major digging work in the site area,
which could have otherwise involved changes in the
levels.
•
The existing top stones of the channels were not to
be changed.
•
According to the brief obtained and as specified in
the instructions given by the Conservation
Architects, maximum efforts were made to design
the system such that the existing invert levels of
the channels would require minimum alteration.
However, to enable water to flow freely by gravity by
providing proper slope, the invert levels i.e. bottom
of the channels required an alteration of 2-3 cm.
•
No new catch-basins, chambers, manholes or pipes
were desirable in the main areas, including the
lawns. Therefore, all the proposed drainage
appurtenances were proposed in the sunken area,
where they would remain out of sight. Since a
minimum amount of disturbance in the garden with
respect to pipes, manholes etc. was desired, no drain
pipe was to be installed except in the sunken area.
In fact, it was decided that the proposed system would
attempt to eliminate the necessity for any manholes,
catch basins etc. to be located within the gardens/
landscaped portions of the site. Since the flow of
water was being proposed to take place in the general
direction from west to east by gravity, no drainpipes
were envisaged in the landscaped area in the final
system.
•
For water to continuously flow at a ‘slow’ speed,
the proposed velocity of water flowing in the channels
was to range from .05 m/s to 0.5 m/s. For this
purpose, the slopes and levels were proposed
accordingly. Certain sections of the channel had
flows varying from 0.02 m/s to 0.15 m/s, due to the
slopes constraint. However, this was not likely to
have a large impact on the visual appeal of the
flowing water.
•
Since there were major variations in the existing
slopes and levels, and also since the water was to
apparently drain out and get wasted in some parts,
the channels at certain sections were extremely
difficult to revive. Therefore, in congruence with the
Conservation Architects, it was proposed to revive
water flow in certain sections of the entire channel
system.
•
The inlet pipe had to be a pressurized pipe and was
taken along the external boundary, however it was
recommended to either take the inlet flow along the
NOVEMBER 2011
internal periphery, or even along the top of the
boundary walls, as they were of sufficient width and
suitable for this purpose. The Conservation
Architects had also suggested the possibility of taking
the inlet pipes along the inner boundary wall beneath
the pathway. But it was found that the inlet pipe
flow along the periphery was preferable. The proposed
inlet points had to be along the northern and
western sides. This also conformed to the historical
aspect, as it is believed this was the natural flowing
pattern of water.
•
Water must re-circulate or else it becomes stagnant
and a source of malady rather than joy. It was
proposed to allow water to flow from the inlet to the
outlet by means of gravity. From the outlet point,
water was re-circulated and diverted back to the inlet
point. This was done using the necessary pumping
equipment. Treatment systems, grit-traps etc. were
proposed based on the water quality and probable
sediment/debris accumulation.
•
Existing grooves and slots in the channels were
utilized for blocking the water from draining out
during periods when recirculation does not take place
to minimize water losses.
Existing Grooves/Slots in the Channel
•
Electricity consumption was to be kept at the
minimum by utilizing suitable mechanical
equipment.
•
It was not viable to revive the whole system with
flowing water, however, it was desired that the major
portion of the inner and middle rings be made
operational. Attempts were made to revive a
maximum portion of the network, in an
economically viable way – both for initial set up and
long-term maintenance. At the main entrance, it
was proposed to revive even the outer channel, as
this area was likely to experience the largest amount
of visual attention from visitors to the monument.
Also, the inlet points had to be located on this
portion of the network.
•
In the north-eastern segments of the channel
system, where underlying terracotta pipes of
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historical significance was present, no proposed
changes were made in the levels, i.e. the existing
levels were to be utilized.
COVER STORY
•
Probably, these fountains were operated with the
help of low-head aqua duct. Therefore, it was decided
that the appearance of the fountains should look
natural and no mechanical equipments should be
visible. Therefore, a small covered sump in one corner
of the tank was located and submersible pumps were
used to re-circulate water through the fountain
heads, which were made up of stone having carving
matching with the original form.
•
These fountains were foreseen to become very
appealing features having the main structure of the
tomb in the background from all four sides – and
splashing water filled the atmosphere with coolness
in the hot northern Indian climate.
Renovation of Fountains
In consonance with the channels, the inlet points were
defined by chaddars, or small waterfalls. Nodes between
the channels would be highlighted by octagonal or
rectangular shallow ponds, which would also have
various kinds of fountains to highlight and enhance
water in various ways. It was decided to install small
gurgling fountains in the four central tanks to give an
appearance, as envisaged in the original feature.
Some other important factors that were simultaneously
considered while working on the project proposal were:
•
Sufficient water should be available for the water
channels, and the losses/wastage of water should
be kept to a minimum so that in the long run the
burden of running the channels would be minimized
and it would also help to ensure that the channels
could become a regular feature of the site and not
merely something kept reserved for special occasions.
•
Rainwater should be utilized for the purpose of
recharging the underground aquifer. The systems
were already in place and only a sensitized system
was to be considered to revive functioning.
Considering well all the main points, suggestions, and
history, the work was executed by the specialized
draftsmen and experienced technicians. The entire
system of channels and fountains was commissioned
and inaugurated by His Highness Aga Khan along with
the Prime Minister of India on 15th April 2003.
A Revisit of Operations
Chaddar
An audit was conducted at the site on 30th April 2011,
with a view to assess the situation of the effects of the
operation and maintenance of the channels and
fountains after functioning for about 8 years. It is a
matter of great satisfaction that after 8 years, the entire
system of channels and fountains is functioning well
in a very satisfactory way and is being maintained as
per the original planning. The hallmark of the success
of the system was perceived to be its low maintenance
requirements and its high degree of self sufficiency.
Four main tanks on the channel network in
which fountains are to be installed.
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The process of systemic design is itself a complex one
and when it is further obscured by trying to read through
450 years of history, it becomes even more convoluted.
For the very term of revitalization of something as
complicated as a historic garden, is almost a misnomer
– as technologies, working methods and ground
conditions change, and all these need to be considered
and evaluated before any decision and proposal is
implemented. To work in a heavily loaded conservation
site, one finds that it is usually advisable to go back to
the ground conditions and stick to the basics - as they
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Some Comparison Photographs (2000 – 2011)
C1 - 2000
C1 - 2003
C1 - 2011
C2 - 2000
C2 - 2003
C2 - 2011
C3 - 2000
C3 - 2003
C3 - 2011
C4 - 2000
C4 - 2003
C4 - 2011
enable a cleaner understanding of the ground reality
and help facilitate the work. And in turn, it is perhaps
this philosophy which allowed this garden of paradise
another new lease at life. IPT
Acknowledgements
-
Mr. Ratish Nanda, Director of Aga Khan Trust for Culture in India,
provided his valued assistance and guidance during the course of
the project.
Archaeological Survey of India was Coordinator of the project.
NOVEMBER 2011
Mr. Mahender Kumar Gupta is
Chairman – IPA New Delhi Chapter. He
is Managing Director of M/s MKG
Consultants and has more than 39 years
of experience in the field of public health
engineering, sanitary engineering and industrial & firefighting
services. He was associated with Aga Khan Trust for Culture
for providing hydraulic services for the renovation of channels
and fountains of Humayun’s tomb. He can be contacted at
[email protected]
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