Well average sediment is about 200 million tones per year plus the sedimentation of last 40 years! (maybe around 8000 million tones). This will be one big dredging operation and I am not sure if it is even feasible.
Tarbela-IV Extension Project[edit]
In September 2013, Pakistan's
Water and Power Development Authority signed a
Rs. 26.053 billion contract with Chinese firm
Sinohydro for executing civil works on the 1,410 MW
Tarbela-IV Extension Project.
[12] Work on the project will be completed in three & half years at an estimated cost of $928 million.
[13] In June 2013, the
World Bank had agreed to provide a $840 million loan for the project.
[14]
The T4 project is being constructed at Tunnel 4 of the dam which was originally intended for irrigation, but was later taken up for power generation as country’s electricity demand increased.
[9]
On completion, the project will increase the generation capacity of Tarbela Hydropower Station to 4,888 MW from the existing 3,478 MW after installation of three units of 1,410 MW on Tunnel No 4.
[12][15] and add about 3.84 billion units cheap electricity to Pakistan's national grid per year. Annual benefits of the project were estimated at about Rs. 30.7 billion.
[13]
Tarbela-V Extension Project[edit]
Prime Minister Nawaz Sharif ordered WAPDA to take up the feasibility study of Tarbela- V Extension Project that would generate additional 1,320 MW electricity and increase the capacity to 6,208 MW. Austrian Government has shown its keen interest to finance the Tarbela-V extension project. Prime Minister also instructed Wapda that Tarbela-IV and Tarbela-V Extension Project be carried out simultaneously.
The original T4 project was estimated to cost $928m, but the project authorities had been able to conclude the project contract at $651m. Since the project cost was much lower than estimates finalised in consultation with the World Bank ($840m), the bank not only approved $51m acceleration programme, but also agreed to divert about $150m, saving another 1,400MW for Tarbela 5th Extension project which is expected to be completed by June 2018.
[9]