Tamilnadu Kallani small History
Kallanai Dam
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 South India.[1] Located at a distance of 15 km from Tiruchirapalli, the dam was originally constructed by the Chola king Karikalan around the 2nd Century AD.
Grand Anicut Place Pictures
Mani Mandapam
Bronze statue of Karikal Cholan king
grand anicut age
kallanai Dam
Built around 2,000 years ago across the Cauveri River in Tiruchirapalli District of Tamil Nadu, the Kallanai Dam is still in excellent condition and used as a major irrigation dam even now. The dam has been inspiration to many modern day dams too due to amazing engineering. Read more to know about this unique example of the amazing architecture and engineering of ancient India.
Built around 2,000 years ago across the Kaveri River in Tiruchirapalli District, Tamil Nadu, by Karikala Chola, the dam was constructed to divert the river to the delta districts thereby boosting irrigation and avoiding loss of crops due to floods.
The dam though very old has a strong foundation and a solid structure. It is still in excellent condition and is used as a major irrigation dam in Tamil Nadu. The dam has also been an inspiration for many recent modern day dams due to its amazing engineering. Due to its impressive architecture, the dam attracts a lot of tourists every year.
The unique structure of the Kallanai dam involves large stones sunk in the Cauvery river to divert the water flow to the fertile delta. The main function of the dam was to retain the water supply in the Cauvery and flow the surplus into Coleroon through the Ullar river. The dam was re-modeled by the British during the 19th century.
In 1804, Captain Caldwell, a military engineer was appointed to promote the irrigation in the delta region. After some study he found out that only a small amount of water was left for irrigation as the maximum water went to Kollidam. Caldwell proposed a solution by raising the dam. Hence, the dam stones were raised to a height of 0.69 meter, which increased the capacity of the dam.
It is believed that floods to an extent of about 5260 cumecs (1,86,000 cusecs) have been discharged through this anicut with minimal or no damage
Cauvery River
The dam is made of unhewn stone and is 1,080 feet long and 60 feet wide, across the main stream of the Cauvery. The area is irrigated by the ancient irrigation network of which the dam was the centrepiece, covering about 69,000 acres. By the early 20th century, the irrigated area had increased to about 1,000,000 acres.
The Lower Anicut built by Sir Arthur Cotton in 19th century AD across Coleroon, the major tributary of Cauvery, is said to be a replicated structure of Kallanai.
Front view of Kallanai
Construction details/observations
The Kallanai was built to divert floods from the Kaveri branch of the river into the Kollidam branch “via a short connecting stream” “when the water level in the river rose above its crest” (Bijker, 2007). The Kollidam “was the wider (also the steeper, straighter, and hence faster) of the two [river] branches, and…the flood carrier. It was barely used for irrigation. Almost all of the 600,000 acres irrigated by the river in 1800 were delta lands south of the Kaveri branch. So the Kaveri branch was the lifeline for delta farmers, while the Kollidam was of little consequence for them” (Bijker, 2007). Once the floods were diverted to the Kollidam, they “[flowed] directly to the sea, causing minimal damage to agriculture” (Bijker, 2007). Figure 3 shows the relation between the Kollidam and Kaveri (labeled “Cauvery”).
Figure 3: Reconstructed map of the Kaveri River around the Kallanai anicut, before 1800. Courtesy of Chitra Krishnan, “Tank and Anicut Irrigation Systems: An Engineering Analysis” (Ph.D. diss., Indian Institute of Technology, 2003).
