Bangkok: The collapse of a protective bund at Pakistan’s Tarbela-5 hydropower project, involving Chinese construction company Power Construction Corporation of China Limited (PCCCL), marked the second major construction mishap since 2025, triggering a sudden surge of reservoir water and forcing authorities to suspend work, a report has stated.
Following Monday’s incident, an emergency was declared, construction activities were suspended, and workers were directed to move to safer locations.
The latest incident comes after an earlier cofferdam collapse at the project in July this year, for which Pakistan’s Water and Power Development Authority (WAPDA) was held responsible, according to a report in Thailand’s daily Page 3 News.
Citing a 15-page report accessed by Pakistani newspaper ‘Dawn’, it said the three-member independent inquiry committee identified unauthorised modifications to the cofferdam design after the contract was awarded as a key factor behind that collapse.
The committee attributed the incident to several actions undertaken outside the scope of the contract and contractual violations involving all three stakeholders.
“It found that the contractor had proposed a cofferdam design alteration that was not permitted under the contract, while the engineer conditionally accepted a design deficiency without ensuring technical compliance. WAPDA subsequently approved the change when construction was nearing completion, without examining its contractual validity or technical shortcomings,” the report in ‘Page 3 News’ mentioned.
The inquiry found that the parties had failed to honour their respective obligations under the civil works and consultancy contracts, contributing to the construction of a structurally vulnerable cofferdam. Its subsequent failure resulted in flooding, project delays and financial losses to the project, the report highlighted
“The stakeholders sought to link the collapse to flooding. However, the committee found that water flows were within annual levels, were not unusual and should have been taken into account in the original design,” it added.
The findings revealed that PCCCL had proposed replacing the original cofferdam design with a rock-filled structure, considered a weaker alternative, across the project, including the channel. The modified structure eventually collapsed, while WAPDA approved the change without assessing its contractual validity.
“Although WAPDA blamed flooding for the incident, the committee said the flows remained within Tarbela’s historical record and were considerably below the cofferdam’s designed capacity. It attributed the failure to inadequate protective layers and filter arrangements,” the report stated.
The earlier collapse delayed the project by at least two years and drove up its estimated cost by more than 285 per cent, from Pakistani rupees (PKR) 82.36 billion to PKR 317 billion, it noted.
(IANS)
