(Date: 12th July 2023)
8th Semester students BSc Civil Engg were taken on a field visit to Malakand III Hydropower project, situated in Dargai, district Malakand.
It consumes 50 cumecs water from river Swat, through a tunnel called Benton tunnel and further conveyed through a penstock of 10 meter diameter. Thus the total fall constitutes of 181 meter. It was started in 1999 and completed in 2004 and since 2008 it is efficiently fulfilling energy needs of its scope area.
Its capacity is 81 MW. It is called Malakand III because it is third HPP in the area. Jabban and Dargai HPPs at Dargai generates 20 MW each. Malakand III is run-of-the-river project. There is no reservoir, no high weir structure involved.
The power generated is 81 MW (Tarbela produces 3500 MW, for reference sake). It is a run-of-the-river project where Tarbela Dam has got a big reservoir because of a 100 meter high weir.
The main pipe is further divided into 3 penstocks leading towards 3 turbines. The 3 penstocks are buried and not visible to eye. The plant has a switch room too.
Fig 1: Road approaching the Hydropower project.
Fig 2: Main Penstock
Fig 3: Turbines (3 in number)
When the turbines are not working due to heavy sediments in water or other maintenances, then the water is diverted to the side channel/fall (Spillway) from the fore bay.
Fig 4: Spillway