Diamer Bhasha Dam is a world class mega-hydro project: Says Chinese Engineer

In an exclusive interview to Gwadar Pro, Yang Haiyan said, facing such a difficult work, has shown confidence. “Since 2003, we have worked for water conservancy construction in Pakistan for 18 years.

We have taken part in the investigation and design of almost all of the hydropower projects in Pakistan, such as Tarbela Dam, Kohala Dam, SK, Gomal Zam Dam, N-J and so on,”

“China’s ability for water conservancy construction is built on years of practice. With our knowledge and experience, we will do our best to live up to Pakistan’s trust,” Yang said.

The construction of the dam will create 16,500 jobs and consume a huge quantity of cement and steel, which will give a boost to the local industry.

The main purpose of the dam is water storage and production of 4,500MW cheap and affordable electricity for meeting the country’s energy requirements.

“Comparing with other world-class mega-hydro stations, DBD can be reckoned as a difficult project,” Yang Haiyan, deputy chief engineer of Bei Fang Investigation, Design & Research Co. Ltd (BIDR), said to the journalist of Gwadar Pro.

DBD was designed as 272 meters height which will be the highest roller compacted concrete (RCC) dam in the world. “DBD will exceed the height of Three Gorges Dam in China (185m), Hoover Dam in the USA (221m), even Itaipu Dam in Brazil (225m),” she said.

Besides, the designed crest length of Bhasha Dam is 1006.5m which can rank among the world-class dams as well. The dam has a normal capacity of 10 billion cubic meters and a regulated (effective) capacity of 7.89 billion cubic meters. Both its installed gross capacity of 4,500MW and average annual energy output of 1.84 trillion watt-hours also ranks among the first class of the world.

In addition to its scale, DBD’stechnical difficulties can be considered as “world-class” as well. In the 1980s, the Pakistani government has started to invite experts to design and consult on the dam. However, due to its technical difficulties are rare in the world, the project has been mired in decades of preparation.

According to Yang’s analysis, there are 6 main difficulties for DBD’s construction:
DBD was located on the upper Indus River. Therefore, its regional geological conditions and structural complexity are arguably the highest in the world.

Barrier lakes are frequently formed in this region. Thus, there will be severe risks brought to project safety and reservoir water storage.

Evaluating the geological conditions and the height of the dam, this project is vulnerable to earthquakes. It means that seismic factors should be considered in the process of material selection and dam design.

Construction of DBD might block Kala Kunlun Highway, the unique arterial traffic in this region. The problem of transportation needs to be solved urgently.
The water head variation rate of DBD is 2.03. It means the highest water head is more than twice the lowest index. It causes it’s difficult to design the turbine units.

The water head of all metal elements of DBS fluctuates in 170-190 meters, even higher than other world-class dams such as Three Gorges. Bearing such great pressure demands higher requirements for a gate design.

She introduced that many world-class hydro projects are made by China. For example, Wudongde Hydroelectric Power Station is the thinnest 300-meter class hyperbolic arch dam in the world. The Merowe Dam in Sudan’s capital is also “made in China”. With a length of 9,285 meters, the dam is the longest dam in the world. Besides, with the biggest comprehensive benefits, Three Gorges Dam is the largest concrete gravity dam in the world.

“China’s ability for water conservancy construction is built on years of practice. With our knowledge and experience, we will do our best to live up to Pakistan’s trust,” Yang said.

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