Periyar Vaigai Major Irrigation Project JI02611
|1||Irrigation Project Name||Periyar Vaigai Major Irrigation Project|
|2||Irrigation Project Name Alias||Periyar System|
|9||Basin||East flowing rivers between Pennar and Kanyakumari|
|14||Work Started in 5 Year Plan||Pre-Plan|
|15||Completed in 5 Year Plan||Pre-Plan|
|16||Project Approval Status|
|17||Year of Approval by Planning Commission|
|18||Approved Cost (Rs. in cr)|
|19||Actual Cost (Rs. in cr)||1.08|
|20||Culturable Command Area (CCA) (th ha)||58.4|
|21||Ultimate Irrigation Potential (UIP) (th ha)||63.2|
|22||Potential Created (PC) (th ha)||63.2|
|23||Project Covered under ERM Scheme||Yes|
|24||Project Covered under CADA Scheme||Yes|
|25||Project Covered under AIBP Scheme||No|
|27||Project Covered under Tribal Sub-Plan|
|28||Project Covered under Drought Prone Area Programme (DPAP)|
|1||Nilayur Bed Dam||Dam|
|3||Perrunai Regulator||Barrage/ Weir/ Anicut (BWA)|
|4||Vagai Pickup Weir||Barrage/ Weir/ Anicut (BWA)|
Periyar Vagai is a Major Multipurpose project as well as trans boundary scheme i.e. involving transfer of water from Periyar river a west flowing river a part of WFR river basin to vagai river which is a east flowing river a part of East Flowing River basin. Periyar is the second largest river of Kerala. It is a west flowing river. Vagai is a river in Tamil nadu which rises on the western slopes of Varushanad hills, at an elevation of 1200 meter in Madurai district and flows in northerly direction.
The natural flow of vagai river basin was already fully utilizsed at the end of 19th Century and water shortage was being experienced. The rainfall in Madurai district being scanty, almost every alternate year scarcity was experienced. On the other hand, along the western ghats, beyond the watershed line rainfall is heavy and water flows into the sea without much utilisation. There was an agreement reached between the Maharaja of Trivandrum and British Government to divert the Periyar water to Vagai basin. According to this agreement, British Government has to pay an annual rent of Rs 4000/- and lease was to run for 999 years, with right to renewal. This led to construction of the Periyar transbasin scheme.
When the Govt of Madras wanted to use the water for Hydro Power generation, a dispute arise between Govt of Madras and Govt of Travancore. The matter went for arbitration. Subsequently after negotiation took place between the two Governments and on 29th May 1970 and agreement was signed between two government which agreement was taken as supplemental deed to the Principal deed of 1886. The new agreement gave fishing right to Kerala Govt, Lake for use of tourism, development of Periyar wild life sanctuary and payment of water used for power generation by Govt of T.N.
The major salient components of the project are as under:
Periyar Vagai Irrigation Project
Periyar Vagai is century old irrigation project. The Periyar dam (Mulla Periyar) was designed and constructed by Colonel John Pennyquick, during 1895. The water is impounded in the Periyar valley which lies in Kerala state and is led from the reservoir through an open cutting 6.40 meter wide to the tunnel over a length of about 1.6 km. A diversion tunnel through western ghats 1.8 km in length was made to acrry water into Vairavanar (tributary of Surliyar) and then into Surliyar river. Surliyar is tributary of Vagai river. The water flowing into Surliyar river is allowed to irrigate about 8099 hectare in Cumbum valley.
During its course of the flow from Cumbum valley, the Periyar water joins the vagai river and is picked up at Peranai Regulator about 145 km below Periyar lake. The Periyar Main canal on the left bank, off taking from Peranai Regulator has a network of 12 branch canal and 64 dis-tributaries.
With the completion of Periyar irrigation project, the ayacut development proceeded fast. The command area was getting converted into fertile land and people could see the large benefits getting accrued due to irrigation. The inflow into Periyar reservoir was also seen to be promising and surpluses were occurring because water could not be drawn across ghat beyond what was consumed for irrigation and was getting wasted, spilling into Arabian Sea. The Idduki reservoir was not in position at the time.There was lot of representation from right bank of the river Vagai as it was not brought under command of Periyar project. Further the tail end of the Periyar command was not getting water. After due deliberation, construction of Vagai dam was undertaken in 1955 and the dam was completed in 1958. The canal on the right bank i.e. Thirumangalam canal was also constructed. The primary purpose of the dam and the reservoir was to regulate the releases from the power station. Due to construction of the dam an additional area of 9238 hectare was also brought under irrigation.
After the construction of Vagai dam the total CCA of the project is 58,500 hectare.
Periyar Hydro-Electric Project
The prospect of developing hydro- Electric power utilizing the head available between Periyar lake level and exit of the tunnel to the east of ghats were know at the time of execution of Periyar project. In the irrigation system already it was planned to construct an intermediate reservoir i.e. Vagai dam to regulate the flow. On the basis of investigation the work of construction of power project was undertaken 1952 and completed in 1955. The total installed capacity is 140 MW (4x35).
Modernisation of Periyar Vagai Project
The area under periyar Vagai project falls under rain shadow area. In order to further increase the command area it was felt to under modernisation of Periyar Vagai project. This work was undertaken under two phases with the help of World Bank. Due to modernisation additional area of 18,300 hectare was under irrigation.
Thus total CCA of the project is now 78,357 hectare.