Ijaz Kakakhel Islamabad
A legislative body of upper house of parliament on Friday was informed that the Delta movement is a constant threat to choke down the Tarbela Reservoirs.
The General Manager Wapda Azam during a briefing on the issue of silting at Tarbela Dam informed the committee that at present the Delta is four miles away from the reservoirs and moves with a speed of 0.25 mile / anum. The information was given during the Senate Standing Committee on Water Resources, which met today in parliament house while Senator Syed Muhamad Sabir was on chair.
While taking briefing on the issue of silting at Tarbela Dam the committee was briefed by the Joint Secretary Ministry of Water Resources that the delta movement is apprehended to hit the structure of the Tarbela Reservoirs. The committee was also cautioned that a sudden earthquake can also increase the potential danger of clogging due to liquefaction of bottom set and fore set slopes would increase as the delta moves closer to the dam.
The committee was apprised that the percentage loss in gross and live storage capacity is 43 pc and 39pc respectively. The committee was further briefed that the option of de-silting of Tarbela reservoir has been considered and its pros and cons have been evaluated that de-silting of Tarbela reservoir will choke the entire irrigations system. Senator Taj Haider expressed reservation on the analysis however suggested Dredging starting from a smaller scale from where it is pivot and the storage of the silting as possible solutions. Senator Taj Haider also pointed that since silting was apprehended in Tarbela Dam, de-silting tunnels were constructed which were never being operated.
The Ministry also informed the committee that the primary purpose of the Tarbela Dam and Mangla Dam is to regulate the flows of the Indus River for irrigation use and not to generate electricity and the power units are also closed for generating electricity. The Secretary Ministry of Water Resources said that through construction of Daso Dam the sediments on the up-streams can be contained which can save the Tarbela reservoir.