Despite slowed down river inflows due to decrease in temperature in catchment areas of Tarbela and Mangla reservoirs, water storage in the country this year is still better as 472,000 acre-feet water is available in the reservoirs for irrigation at present compared with only 185,000 acre-feet water on April 10, 2010.
According to details, water elevation in Mangla reservoir was 1087.1 feet above mean sea level (AMSL) on Sunday against 1067.6 feet on the same date of last year. Water level in Chashma reservoir is 638.15 feet--same as that of last year, while Tarbela reservoir was lower at its dead level ie 1378 feet AMSL. It is pertinent to mention that last year Tarbela reservoir reached its dead level on March 15, about 25 days earlier than currently.
Referring to the decreased water inflows, a Water and Power Development Authority (Wapda) official said that snowfall in the catchment areas of the two mega reservoirs normally starts in November every year. Unusually this year snowing started in the end of January--a delay of almost two and a half months. He said that the unusual decrease in temperature, especially in the hilly areas of the country, during the last two weeks badly affected the rate of snow melting in those areas. Consequently, water inflows, which were on the higher side up till end of March, also reduced. Flow of water in the River Indus at Tarbela is 21,700 cusecs compared with 26,900 cusecs last year. Similarly, mean inflow of water in the River Jhelum at Mangla is 25,600 cusecs against 32,300 cusecs the same day in the 2010, he added.
He said that mercury in the catachment areas of the two reservoirs has started rising. Resultantly, the rate of snow melting will also increase in the days to come. As the inflows become normal, the situation of the water reservoirs, Tarbela in particular, will also improve in a few days, he added.