Kallanai Dam, Trichy
Kallanai (also known as the Grand Anicut) is an ancient dam, which is built (in running water) across the Kaveri river in Trichy District in the state of Tamil Nadu in India. The dam was originally constructed by the Chola King Karikalan in 2nd century AD. Kallanai Dam is the fourth-oldest water-diversion or water-regulator structures in the world and the oldest in India which is still in use.
History
For brief details, please refer below link;
https://tamilnadu-favtourism.blogspot.com/2021/06/kallanai-dam-history.html
Geography
The Kaveri river splits into two at a point 20
miles (32 km) west of Kallanai. The two rivers form the island of
Srirangam before joining at Kallanai. The northern channel is called
the Kollidam (Coleroon); the other retains the name Kaveri, and
empties into the Bengal at Poompuhar. On the seaward face of its
delta are the seaports of Nagapattinam and Karaikal.
The Dam
Kallanai is considered as one of the oldest water
diversion or water regulator structure in the world which is still
functioning. The purpose of the Kallanai was to divert the waters of the Kaveri
across the fertile delta region for irrigation via canals and to its northern
delta branch Kollidam / Coleroon. Downstream of the barrage, the river Kaveri
splits into four streams known as Kollidam Aru, Kaviri, Vennaaru and Puthu Aru.
However, the flood waters can be allowed, by opening the barrage / Anaicut
gates, to pass through the other three delta branches also to join the
sea.
It is constructed from unhewn stone spanning the Kaviri
and is 329 m (1,079 ft) long, 20 m (66 ft) wide and
5.4 m (18 ft) high. The dam is still in excellent condition, and
supplied a model to later engineers, including Sir Arthur Cotton's 19th
century dam across the Kollidam, the major tributary of the
Kaveri. The area irrigated by the ancient irrigation network is about
69,000 acres (28,000 ha). By the early 20th century, the
irrigated area had been increased to about one million acres (400,000 ha).
The dam was constructed in an elegant way to see the dam
from any point. The original dam was built as a check dam. It was built using
unhewn stones that were laid against the flow of the river water to divert the
flow. The dam would limit the water that flowed from the Kaveri into the
Kollidam most of the year while allowing excess water to flow into the Kollidam
during floods. This would allow more water to continue down the Kaveri and into
tributaries and manmade irrigation canals.
The main genius of the original design is that it worked
with the natural flow of the Kaveri and the Kollidam, achieving its results by making
small changes rather than trying to force nature to dramatically change its
course. That allowed the dam to continue to do its work for a thousand and a
half years with minimal upkeep. The
Kallanai dam has stood the test of time, continuing to perform its intended
purpose more than 1800 years after its original construction.
However, the dam hasn’t stood untouched all that time.
As with any modern dam, the Grand Anicut required upkeep. The biggest changes
occurred in the 1800s when the British decided that the dam needed
modernization. The main change was the addition of more stones to raise the dam
and increase the amount of water being diverted. This shouldn’t take away from
anyone’s appreciation of the dam, most ancient dams that are still standing
today have gone through similar updates at some point in their history.
The fact that the original design lasted for around 16
centuries is a testament to the incredible minds of the ancient Indian
engineers who designed the structure. Also, it is said that famed British
irrigation expert Sir Arthur Cotton modeled his own dam designs after the
Kallanai. Today the Grand Anicut is a functioning dam, a tourist destination,
and a symbol of Indian history.
During the years of British rule, it was common for the
intelligence and ingenuity of the Indian people to be downplayed by their
colonial rulers. In truth, the ancient Indians were ahead of their European
counterparts in many ways, and structures like the Kallanai dam have become
important reminders of the region’s rich history. The dam is a source of pride
for residents of Tamil Nadu in particular and Indians in general.
Connectivity
Kallanai Dam is located at about 2 Kms from Thogur, 8.5
Kms from Lalgudi, 9 Kms from Lalgudi Railway Station, 9 Kms from Lalgudi Bus
Station, 12 Kms from Sarkarpalayam, 17 Kms from Trichy Chatiram Bus Station, 18
Kms from Srirangam, 23 Kms from Trichy Central Bus Stand, 24 Kms from Trichy
Railway Junction and 24 Kms from Trichy Airport. From Sarkarpalayam village,
one can take the Sarkarpalayam – Kallanai road and 2 Kms after reaching Thogur
village, lies the Kallanai Dam. Taxis can be hired from Trichy and Lalgudi.