As filling period of dams nears end, water level 11 per cent above normal in Himachal, but 6 per cent below normal in Punjab
Vijay Mohan
Chandigarh, September 22
With the monsoon entering its withdrawal phase and the filling period for dams nearing its end, the combined water level in major reservoirs in Himachal Pradesh is 11 percent above normal, while in Punjab it is six percent below normal.
The filling season for dams is from May to the end of September, coinciding with the withdrawal of monsoon, after which lower temperatures in the mountains decrease the snow melt and consequently reduce inflows.
The water level at Bhakra Dam on Sutlej river in Himachal Pradesh was 510.42 meters against the full reservoir level of 512.06 meters according to the Central Water Commission’s (CWC) weekly bulletin released on September 21. The current storage is 87 per cent of its total capacity. It was 82 per cent at this time last year and an average of 83 per cent over the past 10 years.
At Pong Dam on Beas river in Himachal, the water level was 423.47 meters against the upper limit of 423.67 meters, with the present storage being 93 per cent of its total capacity as compared to 82 per cent last year and 79 per cent over the past 10 years.
Kol Dam, located upstream of the Bhakra which has a much smaller storage capacity, is filled up to 75 per cent of its capacity as compared to 76 per cent last year and an average of 79 per cent over the past 10 years.
The sole reservoir in Punjab located at Thein Dam on Ravi river is filled up to 64 per cent of its capacity as compared to 79 per cent last year and an average of 68 per cent over the past 10 years. The water level recorded at the dam was 516.26 meters against the full reservoir level of 527.91 meters, according to CWC data.
While the reservoirs at Bhakra and Kol are primarily snow-fed, the others at Pong and Thein are primarily rain fed.There have been instances in the past where freak weather events and cloudburst over the catchment areas in autumn, after the official filling season ended, led excess inflows, forcing the authorities to open the dams’ flood gates.
A similar situation had prevailed during the monsoon season this year, when heavy rains led to unprecedented inflows into the Pong Dam, resulting in the water level remaining above the top mark for several days. Release of excess water from Pong and Bhakra had flooded many areas in Punjab.
The monsoon this year, which is now on its last legs, has been above the long period average by 23 per cent in the hill state of Himachal Pradesh, but below par by four per cent in Punjab and one per cent in Haryana till date.
Monsoon has fared poorly during September, with the deficiency being 45 per cent in Haryana, 30 per cent in Himachal Pradesh and 12 per cent in Punjab, according to the India Meteorological Department. Rainfall activity over the region, according to the weatherman, is likely to reduce over the next five days.
