karikalan kattivaithan kallanai
Tank irrigation in Tamilnadu
An irrigation tank
As per a 1996 97 estimate, there are 39,202 tanks in Tamilnadu. In
the past, Chennai alone had about 150 tanks. In Tamilnadu, tank
irrigation has not increased much since 1883, when 50 percent of the
cropped area was under tank irrigation.
Today, less than 10 percent of the land under crops is irrigated by
tanks, built mostly by the Chola and Pandya kings.
Inscriptions in temples tell us of the largesse provided by the kings
for establishing drinking and irrigation water sources.
The Grand Anaicut as it stands now
Anicuts were small or medium dams built across rivers to divert water
into irrigation channels.
The Grand Anicut or Kallanai was built in the second century A.D. by
Karikala Chola. It was made of stone and situated on the river
Cauvery where the River Kollidam branches off.
Anicuts have also been built across the Tambaraparani, Chittar and
many others.
The anicuts in the Kanyakumari district are said to have been built
1000 years ago.
The construction and maintenance was however done entirely by the
people. The Rajasmighamangalam tank of Ramnad was built more than
1000 years ago by the Raja of Ramnad.
Waterbodies in Tamilnadu fall under three categories: lakes or yeris,
tanks or kulams and ponds or kuttais.
A yeri was a large earthenware tank dug out of the ground with the
dug out mud making the side walls or bunds.
A kulam was built with bricks (and occasionally granite) and was
attached to a temple, giving it the name kovil kulam or temple tank.
A kuttai was a small pond. In Tamilnadu there are a few tanks that
irrigate more than 1000 ha and even one which serves 6000 ha. Uranis
are natural springs. Rectangular tanks are constructed above them to
collect the water coming out from the ground. A winding staircase is
provided for people to go down and collect the water for their
domestic use.
The village community decided what crops to grow and where to grow
them, how long the sluice gates of the yeris should be kept open, how
much water should flow to each field and so on.
Tanks can be classified into system and non-system tanks. System
tanks receive plenty of water as they catch the overflow from a
reservoir, nearby stream and the runoff from around their catchment.
They help farmers to raise more than one crop. Non-system tanks
depend entirely on rainfall and can support only one crop. The tanks
used a system of canals and sluice gates to control and transport the
water.
Several tanks linked by canals were also built in the watershed
areas. The surplus of water in the higher tank thus flowed into the
lower one, following the natural slope of the land.
source edited from
http://cpreec.org/04_phamplets/19_traditional_water/traditional_water.
html
