The strategic Second Rehabilitation project of the Warsak Dam and Powerhouse has been delayed for more than three years as the contract for its construction has not yet been awarded. The inordinate delay, caused primarily due to absence of political will, has already resulted in loss of billions of units of cheap energy and significant escalation in project cost due to recent devaluation of the Pakistani currency, besides depriving the nation of various other socioeconomic benefits during this period.
The project PC-1 was approved by the Executive Committee of the National Economic Council (ECNEC) in July 2015, at a total cost of $220.557 million, equivalent to Rs22.254 billion at that time. Project was planned for fast-track implementation; scheduled for completion in seven years. The term of project financing by the donor agencies starts from September 2015 to October 2021, according to approved project construction schedule. International financial institutions i.e. France’s AFD (Agence Francaise Development), the European Investment Bank (EIB) and Germany’s KfW Development Bank have signed agreements to finance the project, as soft-term loan, to the size of 40 million euros, 50 million euros, and 40 million euros, respectively, totaling 130 million euros. In addition, a European Union (EU) grant of 4.5 million euros is available through the AFD for community development around the project area and for the study of the resilience of the Warsak Dam project to climate change.
Constructed during 1952-1960, Warsak Dam along with Powerhouse is the first-ever among the multi-purpose medium and large-sized hydropower plants in the country. Historically, the dam served as a precursor for the large reservoirs and hydropower stations at Mangla (1968) and Tarbela (1977). The Warsak powerhouse had been installed, in first phase, with four turbo-generator units of 40 megawatt each and a 132 kV transmission system. Two additional units of 41.48 megawatt capacity each were commissioned at Warsak during 1980-81, resulting in a 243 megawatt cumulative installed capacity of the powerhouse. All hydraulic turbines for the Canadian-financed Warsak dam and powerhouse were manufactured by Dominion Engineering Co and generators by Canadian General Electric. The first rehabilitation project of Warsak power station was implemented in 1996 under technical and financial assistance of Canada.
During these years, the project, which is located near Peshawar on the Kabul River, has provided important peaking power to the system, and has largely contributed towards improving socioeconomic conditions of the area through electrification and irrigation. The dam had more than doubled the irrigated area adjacent to the river, providing irrigation diversion for 60,000 hectares. While the Warsak power station has been operating largely trouble-free, it has been facing a number of other problems since the early days. One of the major problems is the excessive quantity and abrasive nature of the silt carried by the river water. Operations of the turbo-generating units during the monsoon season with river water, which is laden with silt containing quartz, causes rapid erosion in the turbine parts and other hydraulic equipment, which results in severe and chronic operations and maintenance problems.
Remedial measures like regular repairing and rebuilding the worn equipment and replacement of turbine components are therefore adapted. Still, the powerhouse remains vulnerable to frequent breakdowns due to its ageing and obsolescent machinery, besides the old civil works. There is structural deformation of the powerhouse due to high sediment concentration of the river water, which results in concrete deformation in the building and the spillway. In fact, powerhouse has outlived its designed useful life for quite a long period now, and installed capacity of power station has been de-rated to about 210 megawatt. Yet, the Warsak powerhouse plays a critical role in stabilising the voltage of the national grid later in the year when the output from other hydropower stations drops due to decreased water flows from waterways other than Kabul River. Interestingly, Consultants RSWI/AECOM of Canada who conducted detailed studies on Warsak project in 2013 have suggested phasing out the existing powerhouse, and replacing it progressively with the construction of a new 375 megawatt capacity underground power station that would cost about $400 million.
To achieve high availability and reliability of operations at Warsak Powerhouse it is essential to undertake major overhaul, rehabilitation, upgrading, and replacement of existing hydro-mechanical equipment. Thus the rehabilitation project aims to replace four generators, electrical components of four units, and all power transformers, to install a new state-of-the-art excitation and protection system, and to replace all six turbine runners, in addition to related civil works.
On completion, the installed capacity of the powerhouse will not only be restored to its original designed capacity but would enhance installed capacity to 276 megawatt, enable it to generate an average 1,236 GWh of energy annually. After rehabilitation and upgrade, all the turbo-generating units will be operable for another 30-40 years, thus achieving another lifecycle for the powerhouse.
Pace of work on the Second Rehabilitation project has nonetheless picked up recently, and it would be possible to make up some of the delays in its implementation. Consultants for project management and construction supervision namely Warsak Rehabilitation Consultants, which is a joint venture of lead partner Dolsar of Turkey, along COBA of Portugal and two Pakistani consultants, were appointed in April 2017. They have already finalised tender documents for various lots. International tenders for the main works are expected to be issued shortly. Reportedly, separate tenders are to be issued for (i) powerhouse rehabilitation works including power transformers, and (ii) civil works. Tender for supply and installation of machines for Heavy Mechanical Workshop aiming at upgrading the existing workshop at powerhouse has recently been opened and is being evaluated. Meanwhile, WAPDA has also invited proposals for consultancy services required for climate change adoption strategy.
Warsak reservoir has silted-up and practically there is no live storage available. Dredging of reservoir is not feasible anymore, and power generating plant is operating as a run-of-the-river project. Detailed studies were conducted in the past for establishing a sustainable sediment management concept for the dam and reservoir. Consultancy services for the sedimentation management and related activities to secure intake are being acquired afresh as a major component of the rehabilitation project, for which technical and financial proposals have recently been received by WAPDA, and are under evaluation at present. The study, to be completed by this year, will investigate the present conditions of sedimentation in light of previous studies and propose the adoption of latest methods and techniques to solve the problem. In addition, individual consultants specialising in the fields of civil structure, geological investigations etc are being appointed for the periodic inspection of Warsak Dam.
Warsak project is an important component of WAPDA master plan for optimal utilisation of hydropower resources through undertaking rehabilitation, upgrading, modernisation and capacity expansion of the existing hydropower stations. WAPDA has already completed Tarbela Fourth Extension project, while Tarbela Fifth Extension project is on cards. On the other hand, Mangla Power Refurbishment project is in advanced stage of completion.
To achieve designed installed capacity and to optimise water-flow availability, WAPDA plans to upgrade and modernise a few medium and small hydropower plants as well. Indeed, efficient and forceful implementation of these projects will significantly increase the share of low-cost hydropower generation in the total energy mix, which is the proverbial need of the hour. This will also result in increasing profitability and addressing climate change adaptation issues.
The writer is former chairman of the State Engineering Corporation