Yes silting is a major problem for Tarbela. Dredging is not feasible as it is very expensive. If you suggest to open the floodgates and release silt from there (I am not sure Tarbela dam has this facility like the modern dams)? This will have problems downstream as the barrages will get fair share of this silt and their water storage capacity will be severely reduced.every Dam face this issue specifically during flooding lot of silt sat down on bottom reducing the capacity of the dam to store water best solution to increase the life span is that during winters when water already drops below shut the dame and remove the silt as much as you can but here in Pakistan we already facing electricity shortage can't afford to shut Dam for this purpose which further reducing its life spam and electricity production per year. Currently we have feasible option for Kalabagh but i believe chapter already closed now we have only one solution which is Nuclear plants quite cost effective in a long run but very dangerous also many fault lines run throughout Pakistan and we can't handle Chernobyl like accident. We should gradually reduce line loss by replacing old T & D and should focus on R & D and private sector.