Though there is no increase in the discharge from the artificial lake in Tibet, the threat of massive flash floods in Himachal Pradesh persists. The army and the civil administration remain on high alert.

Also Read Tibet lake prompts alert in Himachal

About 4,000 families from 60 vulnerable locations between Sumdoh in Kinnaur district and Kol Dam in Bilaspur on the banks of the Sutlej river have been evacuated to safer places.

If the swollen Parechu lake bursts, it will send walls of water into the Sutlej river causing unimaginable destruction downstream.

A four-member technical team, comprising two members of the Central Water Power Commission, one blasting expert and a representative of the Nathpa-Jhakri Hydro Project, that was scheduled to visit the site has not yet been cleared by China.

The 1500 mw NJPC remained shut down for the third day on Tuesday.

Though there is no danger to the project, which supplies electricity to northern states, as power house complex at Jhakri is fully underground and located much above the river bed, retaining walls have been erected and gates constructed to deal with any exigency.