Electricity production halted at Upper Tamakoshi due to landslide

Kathmandu, September 28 — The continuous rainfall has caused landslides that have damaged the structures (headworks) of the 456 MW Upper Tamakoshi Hydropower Project in Dolakha's Bigu Rural Municipality-1, Lamabagar.

Due to the high water flow in the Upper Tamakoshi, electricity production has also been halted, and all gates of the dam have been opened.

Damage has been reported to the control room, the sand-thigging basin (desander), and the canal (culvert) that carries water from the dam to the desander, located just below the dam site on the right side. Significant damage is anticipated to these structures due to landslides from above.

Mohan Gautam, the CEO of Upper Tamakoshi Hydropower Limited, stated that flooding in the rivers along the access road from Gongar to the power station has prevented anyone from reaching the site.

He noted that, given the nature of the landslide, damage to the control room, desander, and culvert is expected. The reservoir area has accumulated a large amount of stones and silt due to the landslides.

The design discharge for the Tamakoshi project is 66 cumecs, while the current flow at the dam site is 461 cumecs.

According to the power purchase agreement with Nepal Electricity Authority, electricity production must be stopped if the river flow exceeds 250 cumecs. After the flow surpassed 250 cumecs around 4 PM on Friday, electricity generation was completely halted by 7 PM as the water flow continued to rise.