Bhakra reservoir full, more discharge on way

Vijay Mohan

Tribune News Service

Chandigarh, August 19

With water in rivulets that merge into the Sutlej downstream of the Bhakra Dam subsiding and level in the dam’s reservoir exceeding its permissible limit, authorities at the Bhakra Beas Management Board (BBMB) have decided to increase the quantum of excess water being discharged from the dam. While the BBMB had restricted the discharge to 18,000 to 20,000 cusecs through the sluice gates at the top of the dam over the past three days, it will now discharge an additional 20,000 cusecs over the next few days to maintain the water level within the permissible limit and maintain a buffer for continuous inflows. Besides, an outflow of 36,000 is through the power generation tunnels.

The water level this morning was 1,681 feet against the permissible limit of 1,680 feet. With an inflow of 91,000 cusecs, BBMB officials estimate the level to touch 1,683 feet by late night. Inflow had peaked to 3.11 lakh cusecs on August 18.

“Despite heavy inflows into the reservoir, we had earlier limited the release of water from Bhakra because heavy rains in the region had generated more than two lakh cusecs in rivulets like Sirsa, Swan and Lohand, which lie between Bhakra and Ropar,” a BBMB official said.

“Since there is no forecast of any significant rain over the next seven days, we can now release the excess water in a regulated manner,” he added.

The dam’s filling season lasts till September 30 when monsoon and snowmelt recede and inflows drop. Unforeseen weather events that can bring in deluge also have to be factored in.

Within a span of a year, the dam has witnessed extremities, from being virtually empty last summer with a storage reduced to just seven per cent due to historically low inflows to now managing surplus supply.

BBMB officials said of the 2.40 lakh cusecs that passed downstream of Ropar, only 19,000 cusecs had been released from sluice gates. An official said minimum possible water would be released through the sluice gates and the quantum being released would not result in any adverse situation downstream.

At Pong Dam, which is also witnessing inflows of 91,000 cusecs, the water level is 1,375 feet against the limit of 1,390 feet. The BBMB has suspended power generation at Pong to stop discharge downstream into the Beas that could minimise flooding at the Harike barrage.

‘14% outflow from sluice gates’

We tried to restrict and delay the release of additional water from sluice gates and even during peak inflows, gates were opened to the extent of only 6%. With situation downstream now improving, water release will be 14% of the gate's total capacity. — A BBMB official

How much water to expect

• 20,000 cusecs additional to be released in next few days
• 18,000-20,000 cusecs already being released via sluice gates
• 36,000 cusecs being released via power generation tunnels
• 91,000 cusecs current water inflow into Bhakra reservoir