| Ponmudi Dam | |
| Image Caption: | Ponmudi dam and reservoir |
| Dam Crosses: | Panniyar river |
| Res Name: | Ponmudi Reservoir |
| Location: | Idukki, Kerala |
| Plant Turbines: | 2 x 16.2 MW (Francis-type) |
| Plant Capacity: | 32.4 |
| Plant Annual Gen: | 158 MU |
| Coordinates: | 9.9603°N 77.0567°W |
| Location Map: | India Kerala#India |
| Website: | Official website |
| Status: | O |
| Purpose: | P |
| Country: | India |
| Owner: | Kerala State Electricity Board |
| Spillway Type: | Ogee type |
| Spillway Count: | 3 nos, radial gates, each of size 10.97 x6.4 m |
| Plant Name: | Panniar Power Station |
| Plant Operator: | Kerala State Electricity Board |
| Plant Coordinates: | 9.9731°N 77.0281°W |
| Spillway Capacity: | 1416.3 m³/s |
| Dam Type: | G |
The Ponmudi Dam is a concrete gravity dam built across the Panniyar river which is a tributary of Periyar river at Konnathady panchayath of Konnathadi village in Idukki district of Kerala, India. The dam was constructed in 1963 as a part of a hydroelectric project. Construction was led by E.U.Philipose, Superintending Engineer, Kerala State Electricity Board. It has a length of .[1] The hydropower component of the dam has an installed capacity of 30 MW with firm power of 17 MW, generating 158 GWh annually.[2] Taluks through which the river flow are Udumbanchola, Devikulam, Kothamangalam, Muvattupuzha, Kunnathunadu, Aluva, Kodungalloor and Paravur.
The dam, located near Munnar on the Panniar river in the Periyar river valley in Kerala, is part of the basin of the West flowing rivers of the Tadri to Kanyakumari. The nearest city is Udumbanchola.[2] [3] Mattupetty to Ponmudi dam is a distance of .[4]
The Ponmudi dam is a masonry gravity dam of height with a total length of . At the Full Reservoir Level, the gross storage capacity of the reservoir is and live storage is . The dam has a total volumetric content of . The dam is located in Seismic Zone-III. The reservoir water spread area or submergence area is . The spillway is designed for a design discharge of per second. The flood discharge is routed through a spillway which is fitted with three radial gates, each 10.9728x.[2] [5] [6] The stored water is diverted through a tunnel of for power generation creating a head of .[5] [7]
The water stored in the reservoir is utilized for power generation by diverting the flows through a 3066m (10,059feet) tunnel[8] followed by two lines of penstock pipes each with a diameter of and a length of . The two penstock pipe lines are designed to carry a discharge of per second. The power station located at Panniyar is provided with installation of 30 MW comprising two units, each of 15 MW capacity Francis turbines. The firm power generation is 17 MW and the annual power generated is 158 GWh. The first unit was commissioned on 29 December 1963 and the second unit on 26 January 1964. The units were renovated in 2001 and 2003.[5] [9]
In a major disaster at the project site, which occurred 17 September 2007, one of the penstock valves burst causing the death of 7 people, destroying 15 houses, and damaging of crops. The reason attributed to the pipe burst is the loosening of the flange bolt connection. The damaged valve was rectified in July 2009.[5] [10] [11]