India’s Ministry of Power is closely monitoring the aftermath of flash floods in the Teesta Basin of Sikkim, which has left a significant impact on central hydro power projects in the region. In an emergency meeting held on Wednesday, Shri Pankaj Agrawal, Secretary (Power), along with senior officials from the Ministry of Power and the Central Electricity Authority, discussed the situation with the National Hydroelectric Power Corporation (NHPC).

The flash floods, occurring in the night of October 3rd and 4th, 2023, resulted in the submersion and destruction of all bridges downstream of the Teesta-V Hydropower Station up to Tarkhola/Pamphok. This has had a severe impact on transportation and communication in the affected areas. The floodwater overtopped the dam of the Teesta V Power Station, with all roads leading to the project sites and parts of the residential colony sustaining significant damage. As a result, the power station is currently shut down and not producing electricity, with NHPC evacuating its workforce on all projects and ensuring their safety. Tragically, one casualty was reported from the Teesta V power station.

The ongoing construction of the Teesta VI hydro project, which has a capacity of 500MW, has also been disrupted by the flooding. The floodwaters infiltrated the powerhouse and transformer cavern, while key bridges connecting the right and left banks of the barrage and the Power House were washed out. Two crane operators working on the project site are currently missing, and all possible efforts are being made to locate them.

While the Teesta Low Dam - III Hydropower Plant (TLDP-III) and TLDP-IV, both located in downstream West Bengal, did not suffer major damage, they remain shut down due to heavy siltation brought by the floodwaters. NHPC is working to restart electricity generation at both of these projects in the coming days. Fortunately, no damage has been reported in the Rangit valley, where NHPC's Rangit IV power project and Rangit Power Station are situated.

A detailed assessment of the extent of damage at all project sites will be carried out once the water levels recede. NHPC, in collaboration with the state government, disaster management authorities, and the district administration, is making every possible effort to maintain the supply of essential commodities such as food, medicine, and electricity to the affected regions.

The Central Government has committed to conducting a thorough evaluation of the damage to these vital hydropower projects as the floodwaters recede. NHPC said it is working tirelessly to expedite the restoration of these projects, ensuring that they are operational at the earliest opportunity.

by waterpowermagazine