Reservoirs in Tamil Nadu are associated with dams in the state. They are structures which store or reserve water of the rivers, which is distributed in Tamil Nadu to be consumed by the people. The accumulated water is a major requirement for the growth of crops in the agricultural fields and production of electricity. Some of the reservoirs in Tamil Nadu are described below.
Pechiparai Reservoir
Pechiparai Reservoir is located about 43 km from the town of Nagercoil, close to the village of Pechiparai in Kanyakumari district of Tamil Nadu. The reservoir is associated with Pechiparai Dam, which has been constructed across Kodayar River, about a mile downstream of the confluence of the tributaries of Kallar, Chittar and Kuttiyar. The catchment area of the reservoir is around 207.19 square kilometers and its depth is almost 14.63 meters. The water of Pechiparai Reservoir is used both for irrigation and also for drinking purposes.
Vattamalaikarai Odai Reservoir
Vattamalaikarai Odai Reservoir is situated in Uthamapalayam. The construction of this reservoir was initiated in the year 1974 and was completed in the year 1981. Vattamalaikarai Odai Reservoir provides water for irrigation purposes to about 6,024 acres of land. During the monsoon season, water up to 20ft. is stored in the reservoir.
Aliyar Reservoir
Aliyar Reservoir has been constructed across Aliyar River. It is situated close to Pollachi in Coimbatore district of Tamil Nadu. Aliyar Reservoir Project being a micro hydel scheme is backed financially by the Ministry of Non-Conventional Energy Sources of the Government of India.
Varadamanadhi Reservoir
Varadamanadhi Reservoir is situated in Dingul district of Tamil Nadu. It has helped to bring about agricultural development in the district of Dindigul. Varadamanadhi Reservoir has also made significant contributions towards the National Agriculture Production.
Sholayar Reservoir
Sholayar Reservoir has been constructed in close proximity to Valparai. The plateau where this reservoir has been constructed receives heavy rain throughout the year. During the rainy season, the water level in the reservoir reaches almost 162.77 feet against the full reservoir level of about 160 feet.
Chittar Reservoir
Chittar Reservoir has been constructed on Chittar River. This reservoir is one of the major sources of water for irrigation in the surrounding areas. More specifically, the dam irrigates about 8,903.27 hectares of land. Chittar Reservoir has become one of the most favorable tourist destinations in Tamil Nadu.
Stanley Reservoir
Stanley Reservoir is one of largest fishing reservoirs in south India. The source of water of this reservoir is Kaveri River. The water of Stanley Reservoir is held back by Mettur Dam. The total capacity of Stanley Reservoir is more than 90,000,000,000 cubic feet. This reservoir is one of the largest of its type in India and its construction was completed in the year 1934.
Kodaganagar Reservoir
Kodaganagar Reservoir has been constructed on Kodagananar River. This reservoir serves the entire river basin expanding to almost 2000 square kilometers. The water of Kodaganagar Reservoir is mainly used in the district of Dindigul and in a small part of the district of Karur in Tamil Nadu.
Thirumurthi Reservoir
Thirumurthi Reservoir is a moderately productive reservoir at the tail end of the Parmabikulam Aliyar System. This is a small reservoir and its construction was completed in the year 1966. Thirumurthi Reservoir is the breeding place for many fish species.
Kullursandai Reservoir
Kullursandai Reservoir has been constructed over Kowsiga Mahanadi, a tributary of Arjuna Nadi. This reservoir is situated in the district of Virudhunagar. Kullursandai Reservoir is one of the notable tourist destinations of the region.
Varattupallam Reservoir
Varattupallam Reservoir is situated at Varattupallam, close to Anthiyur in Tamil Nadu. This reservoir has a water capacity of about 3 TMC ft. Varattupallam Reservoir usually stores more than 30 feet of water. The water of the reservoir is mainly used for irrigation. This reservoir is eventually depleting due to scarcity of rain in Bargur Hill area.
Manjalar Reservoir
Manjalar Reservoir in Tamil Nadu caters to the water requirements of the district of Madurai. The reservoir is very small in size and it mainly acts as a breeding place for tilapia fishes. Almost 80 percent or more of the fishery production in Tamil Nadu is bred at Manjalar Reservoir. 
Periyar Reservoir
Periyar Reservoir has been constructed on Periyar River, submerging 26 square kilometers of evergreen forest. It was set up in the year 1895. The Mullayar and Periyar river systems drain the catchment area of the reservoir. The altitude of the reservoir ranges from 79 to 1,987 meters and the annual average rainfall experienced at the reservoir site is about 3,289 mm.
Bhavanisagar Reservoir
Bhavanisagar Reservoir is situated in Bhavanisagar in the district of Erode in Tamil Nadu. The height of this reservoir is around 32 meters and the capacity of the reservoir is around 32.8 TMC.
Krishnagiri Reservoir
Krishnagiri Reservoir was founded upstream of Sathanur Dam. Even if Krishnagiri Reservoir occupies the same area as that of the dam, the reservoir is much shallower than the dam.
Vidur Reservoir
Vidur Reservoir is regarded as the shallowest of all the reservoirs in Tamil Nadu. The average depth of Vidur Reservoir is about 2.1 meters.
Pambar Reservoir
Pambar Reservoir was constructed on Pambar River. This reservoir stands at an altitude of about 1,400 feet.
Other Reservoirs in Tamil Nadu
Willingdon Reservoir has been constructed on Periya Odai River. Amaravathi Reservoir is situated at Amaravathinagar. The water of Chalakudy River forms the Thunakadavu Reservoir. Gundar Reservoir is one of the most beautiful and unspoiled spot in Tamil Nadu.