<P> Because of revised lower costs to $651 million from $928 million, the World Bank permitted Pakistani officials to expedite completion of the project by 8 months at a cost of an additional $51 million . Pakistani officials were also permitted to divert $126 million towards the Tarbela - V Extension Project . </P> <P> The Tarbela Dam was built with five original tunnels, with the first three dedicated to hydropower generation, and the remaining two slated for irrigation use . The fourth phase extension project uses the first of the two irrigation tunnels, while the fifth phase extension will use the second irrigation tunnel . Pakistan's Water and Power Development Authority sought expressions of interest for the Tarbela - V Extension Project in August 2014, and was given final consent for construction in September 2015 . </P> <P> Construction is yet to begin but will require an estimated 3.5 years for completion . The project will require installation of three turbines with a capacity of 470 MW each in Tarbela's fifth tunnel which was previously dedicated to agricultural use . Upon completion, the total power generating capacity of Tarbela Dam will be increased to 6,298 MW . </P> <P> The hydro power project of tunnel 5 has two major components: power generation facilities and power evacuation facilities . The major works included under the project are modifications to tunnel 5 and building a new power house and its ancillaries to generate about 1,800 GWh of power annually, a new 50 km of 500kV double - circuit transmission line from Tarbela to the Islamabad West Grid Station for power evacuation, and a new 500kV Islamabad West Grid Station . </P>

Which of the following is not true about the tarbela dam