Guwahati: Water discharge in the Subansiri River rose sharply after midnight on July 13 following heavy inflows from upstream areas, according to the Subansiri Lower Hydroelectric Project (SLHEP).
The project said flood early warning systems installed at Daporijo on the Subansiri River and Tamen on the Kamala River detected rising water levels and issued alerts nearly six hours in advance.
Following the alerts, the district administrations were informed, and sirens were sounded around midnight to warn people living along downstream riverbanks about the expected rise in river flow.
According to the project, river discharge increased from about 7,000 cumecs shortly after midnight to a peak inflow of around 13,000 cumecs at 10:45 am.
The project said the Subansiri River has a safe carrying capacity of about 7,000 cumecs. It stated that the reservoir of the 2,000 MW Subansiri Lower Hydroelectric Project reduced the peak inflow of around 13,000 cumecs to an outflow of about 12,000 cumecs at around 11 am, which helped delay and reduce the downstream flood peak.
The river discharge later showed a declining trend and fell to around 7,500 cumecs by the evening.
The project also said local television reports indicated that the advance flood warnings and flood moderation measures helped downstream communities prepare in advance and reduced the impact of the high river flow.