El Nino is a modern term but
our land of ancient Tamils had always experienced heavy rains in the solar
months of Aippasi and Karthigai. This is made out from the adage “Aippasiyil adai mazhai, Karthigaiyil Gana mazhai”( ஐப்பசியில் அடைமழை, கார்த்திகையில் கனமழை).
The Paripaadal verse on Pavai Nonbu (verse no
11) describes a scene of flood ravaged land that comes to house smaller water
bodies called “KuLam” by the time the month of Margazhi
begins. For this reason the month of Margazhi was also known as “KuLam” (குளம்).
Our ancestors have laid a
fantastic system of hydrology to channelize the flood waters and also to store
the excess water for use in dry months. This network can be depicted as below.
(Note: Click on the pictures to see enlarged version)
The network comprises of
River water overflowing into subsequent and smaller water bodies.
River > Lakes (Yeri) >
KaNmai > KaraNai > Thaangal > Yenthal > OoraNi > KuLam >
Kuttai.
These names themselves show
that Pazhavanthaangal and Vedanthaangal were water bodies once. Even now there
are some street names as Thaangal street in
different parts of Chennai. It means there was once a water body adjacent to
that street.
The topography
and hydrology of Chennai is such that Chennai is a low lying area with
an average elevation of only 6.7 metres above
the mean sea level, with many parts of it actually at sea level. This landscape of Chennai makes it a marshy land that
drains rain water into the adjacent sea. Chennai was indeed dotted with
numerous tanks and lakes as per old maps of the British. Agricultural activity
was going on at that time supported by these tanks.
The oldest map that I could
get from a Google search was of
1893. It shows a long semi curved tank spanning in between Coovum river
and Adyar river. (Below)
At that time this tank was
identified at two places (in the map) as Nungambakkam tank and Mylapur tank. The ‘Long Tank Regatta’ was held in 1893 “on
the fine expanse of water that starts from the Cathedral Corner (once where
Gemini Studio’s property was) to Sydapet”.
The southern end of this
tank is linked to Adyar river near Saidapet. The map of 1914 gives clear details of this tank
which by then acquired the name “Long Tank”. The inset in the 1914 map (below)
shows that this link between Long tank and Adyar river is man-made. This must
have existed much before the British came. This is the proof of how our
ancients thoughtfully connected the waterways and the drainage system.
The Vyasar
padi tank in this map was also a huge one at that time. But it is
missing at present. The Vyasarpadi Tank was one of the most important tanks of
Chennai along with 9 other tanks namely Perambur, Peravallur, Madavakkam, Chetput, Spur, Nungambakkam,
Mylapore/Mambalam, Kottur and Kalikundram.
All of them have vanished
now.
The
first official encroachment of water bodies in Madras started in 1923
with the plan to reclaim land from the Long Tank. The party that was in power
at that time was none other than the root cause of the Dravidian ideology namely
the Justice Party. The
party that was unambiguously based on anti-Brahmanism and atheism and had brain
washed the masses with a non-existent Dravida ideology found no qualms in
destroying a major water source of Madras.
Reclamation of land from this tank was
started from 1930 by the
same Justice Party, to create the Mambalam
Housing Scheme on 1600 acres that gave rise to Theagaroya Nagar or T. Nagar
(named after the founder of Justice Party). Destruction of hydro system in the name of development was started by
these Dravidian ideologists.
From 1941 onwards, further reclamation
was done in Nungambakkam. At the westernmost end of the Tank, 54 acres were
reclaimed for the Loyola College campus.
In 1974 what was left of the Tank was
reclaimed to give the city the Valluvar Kottam campus alongside Tank Bund Road by none other
than Karunanidhi.
It must be noted that Valluvar
Kottam was constructed right at the deepest part of the Long Tank. Old
timers recall that for many years and year after year, Valluvar Kottam was
water logged during the rainy season. It would have been apt had they named it as Valluvar Ottam or Valluvar
Theppam (Float)!
The following map is that of Chennai
today. The location of the missing Long Tank
(rough sketch) is shown in the next map.
The Long Tank formed the
western boundary of Madras of those years. The Mount road was laid to the east
of it. Today’s Mambalam, Mylapore, Panagal Park, Nungambakkam etc were built on
this Tank. No wonder when
Adyar river overflowed, the waters found their natural slopes in these areas in
the recent floods.
A map
drawn 65 years ago shows a
sprinkle of numerous water bodies such as Yeris and Kulams all over present day
Chennai. They were also well connected to drain extra water in times of flood. This
map is shown below.
The gray areas are the water
bodies which would remain dry in summer but can house rain water in the rainy
season.
Today the gray areas are all
closed down with habitations. Needless to say why most parts of Chennai is
water logged even by short spell of rains.
The presently available
water bodies –from among the network in the above map - are shown in the
picture below.
In a good monsoon year,
where will the rain water go? All the gray areas become water logged.
A compilation of
reports on areas of Chennai which were once water bodies or drainage canals.
·
Two main rivers Cooum
and Adayar cross Chennai. Chennai’s
periphery once hosted a massive wetland,
which provided a natural flood control barrier in the past.
·
Adyar,
Cooum, Kosasthaliyar and the man-made
Buckingham canal are the macro drainages. They
have a huge capacity to carry flood waters which is by now reduced to half the
capacity due to encroachments.
·
The river Coovum which was once a fresh water source is now
reduced to a massive,
stinking sewer heaped with the
waste generated by a heaving metropolis.
·
Similarly, rampant
encroachment and urbanisation in its upstream reaches has sapped
the ability of the Adyar river to carry flood water.
·
Another key waterway,
the Buckingham Canal, is also choked with silt
and sewage. So, when Chennai floods, there aren’t enough unobstructed channels
for the water to get out.
·
Around eight
medium drainage canals drain in to these rivers. These are the Otteri Nallah, Virugambakkam canal, Arumbakkam canal,
Kodungaiyur canal, Captain Cotton canal, Velachery canal, Veerangal Odai and Mambalam
canal. They are all missing now.
·
Two decades ago,
Chennai had 650
water bodies—including big lakes, ponds and storage tanks. The current number stands at around 27,
according to the NIDM study. Even those water bodies that have managed to
survive are much smaller than before. For instance, the total area of 19 major
lakes in the city has
nearly halved from 1,130
hectares to about 645 hectares.
·
Other water bodies such
as Ullagaram, Adambakkam, Thalakanacheri, Mogappair and
Senneerkuppam are considered beyond restoration. In the case of water
channels like inlet and outlet they have completely disappeared
·
There are about 3000 tanks and ponds big and small in the Chennai
area. Some of the important tanks are Madipakkam,
Velachery, Thoraipakkam, Pallavaram, Madambakkam,
Maraimalainagar, Kilkattalai, Pallikaranai, Adhambakkam, Puzhudhivakkam,
Thalakanancheri, Kovilambakkam, Chitlapakkam
and so on. These tanks can be classified as ENDANGERED.
·
The Adambakkam Lake is being closed due to the Metro Rail
work and a concretised road leading from Velachery to GST Road is being built.
·
Madipakkam
Lake has become a dumping yard for garbage
and the water is not fit for any use. And on the other side construction of
buildings is going on apace.
·
Puzhudhivakkam Lake was
once an important reservoir and used to host a number of rare birds. This
valuable natural resource has now been gradually converted into a housing
colony. Inundation in Puzhudhivakkam and Madipakkam is caused by the
disappearance of the Veerangal Odai which connects the Adambakkam and the
Pallikaranai marsh.
·
Chitlapakkam
Lake was once the water source for the
Sembakkam and Hastinapuram villages. The total area of this lake is 86.86 acres
which has subsequently shrunk to 47 acres due to encroachments such as the
development of the district court, bus terminal and the Tambaram taluk office.
·
Chitlapakkam lake is
getting water through 3 channels from the foothills. However, in this region
the water table level is higher than in other areas. This lake is further
contaminated by household sewage and waste from commercial establishments.
·
Chennai,
Thiruvallur, Kancheepuram and Chengalpattu are hydrologically integrated. As
per the tank memoir prepared by the British, there are 3,600 tanks in these
districts and the surplus from around 20 tanks have
also contributed to inflow in Chembarambakkam. All these have been encroached now.
·
Pallikaranai marshlands,
which drains water from a 250 square kilometre catchment, was a 50 sq km water
sprawl in the southern suburbs of Chennai. Now, it is 4.3 sq km—less than a
tenth of its original.
·
Pallikaranai marsh
acted as a natural flood sink when the rains overwhelmed Chennai. “The marsh
that was till about 30 years ago spread over an area of more than 5000 ha
(hectares) has been reduced to around one-tenth of its original extent due to
anthropogenic (manmade) pressures. The free flow of water within the entire
marsh has been totally disrupted due to mega construction activities and
consequent road laying,” a 2007
study by a group of German and
Indian scientists noted.
·
The growing finger of a
garbage dump sticks out like a cancerous tumour in the northern part of the
marshland.
·
Two major roads cut
through Pallikaranai waterbody with a few pitifully small culverts that are not
up to the job of transferring the rain water flows from such a large catchment.
The edges have been eaten into by institutes like the National Institute of
Ocean Technology (NIOT). Ironically, NIOT is an
accredited consultant to prepare environmental impact assessments on various
subjects, including on the implications of constructing on water bodies.
·
There were 16 tanks
downstream of Retteri called Vyasarpadi chain of
tanks. Kodungaiyur tank was one among them. Now,
there is no sign of them.
·
There was also a tank
in Thirumangalam area which is missing now.
·
There were once 13
water bodies in Neelankarai (the name itself
shows that this place was on the banks of a water body). Only 2 lakes remain
now.
·
The Virugambakkam drain was 6.5 km long and drained into
the Nungambakkam tank. It is now present
only for an of extent of 4.5 km. The remaining two km stretch of the drain is
missing.
·
Nungambakkam
tank (part of Long Tank) was completely filled
and built. This along with the loss of Koyambedu drain has resulted in the
periodic flooding of Koyambedu and Virugambakkam areas.
·
The surplus channels
connecting various water bodies in western suburbs such as Ambattur and Korattur have been encroached upon.
·
The water body in Mogappair has almost disappeared.
·
The Veerangal Odai that connects the Adambakkam lake with
Pallikaranai marsh ends abruptly after 550 m from its origin and the remaining
part is not to be seen. This causes inundation in places such as Puzhithivakkam and Madipakkam.
·
The Chennai Bypass connecting NH45 to NH4 blocks the east
flowing drainage causing flooding in Anna Nagar, Porur,
Vanagaram, Maduravoyal, Mugappair and Ambattur.
·
The Maduravoyal lake has shrunk from 120 acres to 25
acres. Same with Ambattur, Kodungaiyur and Adambakkam
tanks.
·
The Koyambedu drain and the
surplus channels from Korattur and Ambattur tanks
are missing.
·
The South Buckingham
Canal from Adyar creek to Kovalam creek has been squeezed from its original width
of 25 metres to 10 metres in many places due to the
Mass Rapid Transit System railway stations.
·
Important flood
retention structures such as Virugambakkam, Padi and
Villivakkam tanks are no longer there.
·
Elevated
Express freight corridor from Chennai harbour
to Maduravoyal had reclaimed a
substantial portion of the Coovum’s southern bank drastically reducing the
flood-carrying capacity of the river.
·
The lost water body of Velacheri between the year 2000 and 2015 is shown
below.
·
The two drainage canals
that went missing when I.T park was developed in Siruseri.
·
Water bodies shrunk by
the Sholinganallur I.T park is shown below.
·
A comparison of the
Chennai topography with the missing Long Tank is shown below. In the figure, No1 shows Coovum river. No 2
shows Adyar river. Where is No 3?
The
lesson
We have robbed the natural habitation of Chennai’s
water routes. They have paid us back.
***********
Sources for this
compilation:-
