World Bank considering to finance T4HP

World Bank is considering to provide financial assistance for Tarbela Fourth Extension Hydropower Project (T4HP) to facilitate a sustainable expansion in Pakistan's electricity generation capacity, which will be completed at a cost of $900 million. In Environmental and Social Assessment, the bank said that without-project scenario was not acceptable since this would seriously deteriorate the shortage in power production in the country.
According to the report, the T4HP will require water to be diverted from the existing irrigation tunnel to the new powerhouse. This new arrangement will be designed so that the irrigation capacity of Tunnel 4 will be unaffected. An equal diameter bifurcation will be constructed from the existing tunnel, which will be connected through a curved penstock with a new powerhouse to be constructed. In the powerhouse three 450 MW turbines will be installed. The T4HP project consists of five components.
According to the report, the Construction of Powerhouse and Modification of Tunnel will be completed with the total cost of $278.9 million. This component consists of the civil works for construction of a powerhouse suitable for three 450 MW units, the penstock arrangements and the modifications needed in the tunnel intake and outlet structures. The powerhouse will be constructed at a location close to the hillside on the Right Bank somewhat upstream of the current outlet gates. The penstock between the tunnel and the powerhouse will then be as short as possible. By selecting this site the powerhouse will be founded on relatively stable rock.
There will be a new independent bypass constructed to facilitate the irrigation flow. There is limited space near the steep hillside and at places the slope near the powerhouse and/or the outlet of Tunnel 4 has to be cut back and to be stabilised with rock anchors, wire mesh and other protection measures. For the existing road on the right bank a new alignment has to be found. The inlet structure of Tunnel 4 will be provided with a raised intake (el. 415 m) in order to maximise the operational life of the tunnel and to avoid blockage of the present low level inlet. The higher intake will be connected through a shaft with the upstream part of the tunnel.
Furthermore, the Power Units and Ancillary Equipment project component will be completed with the total cost of US $402 million. This component covers the installation of turbines, generators, transformers, ancillary electro mechanical equipment and a short transmission line to connect to the grid.
Environmental and Social Action Plan, Dam Monitoring and Surveillance would required $29 million. This covers the implementation of a Social Impact Management Framework. A part of the component will require $15.0 million to address the resettlement legacy issues related to the Tarbela and Ghazi-Barotha projects, to prepare an Information and Communication Plan and a Public Health and Safety Plan. Also a reach out programme will be prepared in order to provide technical assistance (eg upgrading infrastructure, health facilities) to resettlement communities in the area.