NHPC restarts two units of Teesta Stage V hydro project after 2023 GLOF
NHPC has resumed commercial operations at Units One and Two of Teesta Stage V Hydroelectric Power Station, restoring 340 MW to India’s grid after the October 3–
NHPC has restored commercial operations at two generating units of its Teesta Stage V Hydroelectric Power Station in Sikkim, nearly three years after a catastrophic glacial lake outburst flood (GLOF) affected the Teesta basin. The restart brings back 340 megawatts of generation capacity to India’s electricity grid.
Units One and Two, each with an installed capacity of 170 megawatts, resumed commercial operation at 5 p.m. on July 13 following successful synchronization with the national grid. NHPC said the third generating unit will be commissioned separately, after which the station can return to its original total capacity.
Commissioning of the remaining unit still pending
With two units now operating, Teesta Stage V is temporarily short of its full 510-megawatt installed capacity. NHPC stated that the third unit, which would add the remaining 170 megawatts, will be taken up for commissioning on a separate schedule.
Infrastructure rebuilding after the 2023 flood
The GLOF occurred during the night of October 3–4, 2023, when South Lhonak Lake breached and released a destructive surge through the Teesta valley. The flood severely damaged hydropower infrastructure and disrupted key areas along the basin. NHPC reported that the Teesta Stage III dam at Chungthang was destroyed, while roads, bridges, and communities in the region also faced major impacts.
NHPC estimated direct losses from the flood at Rs 1,075.97 crore. Restoration work later faced another setback in August 2024, when a landslide damaged the outlet structure of the project’s tail race tunnel. NHPC estimated additional losses of Rs 327.67 crore, extending the timeline for full restoration.
Engineers carried out civil reconstruction and repairs to hydro-mechanical systems and electrical equipment. They also rehabilitated critical infrastructure needed for the station to return to commercial service. NHPC said the restart of two units is a key milestone in the gradual recovery of the region’s hydropower corridor and its renewable power supply.
