Mullaperiyar Dam

About Mullaperiyar Dam

• It is a masonry gravity dam situated on the Periyar River in Thekkady, Idukki district, in Kerala.
• It is located 881 m above sea level, on the Cardamom Hills of the Western Ghats.
• The dam is built at the confluence of the Mullayar and Periyar rivers.
• Its construction began in 1887 and was completed in 1895. The construction was carried out by the British Corps of Royal Engineers under the leadership of Pennycuick.
• It has a height of 53.6 m from the foundation and a length of 365.7 m.
• The dam was constructed with limestone and “Surkhi" (burnt brick powder and a mixture of sugar and calcium oxide).
• The dam's purpose was to divert the waters of the west-flowing River Periyar eastward to the arid rain shadow regions of the Theni, Madurai, Sivaganga, and Ramanathapuram districts of Tamil Nadu. 
• The Periyar National Park is located around the dam's reservoir. 
• Although the dam is located in Kerala, it is operated and maintained by the neighbouring state of Tamil Nadu. It was according to a 999-year lease agreement made during the British rule that the operational rights were handed over to Tamil Nadu.

Q1) What is a gravity dam?

A gravity dam is a type of dam structure that is primarily designed to resist the force of gravity and hold back water or other materials. It relies on its own weight and mass to counteract the horizontal pressure exerted by the water or other materials it is retaining. Gravity dams are among the oldest and most common types of dams used for various purposes, including water supply, irrigation, flood control, and hydroelectric power generation.

Source: Tamil Nadu cancels shutter opening of Mullaperiyar dam