A protective bund collapse at Pakistan's Tarbela-5 hydropower project has marked the second major construction mishap at the site since 2025, triggering a sudden surge of reservoir water and forcing authorities to suspend all work. The incident involves Power Construction Corporation of China Limited (PCCCL), the Chinese contractor overseeing the project, and has renewed scrutiny over construction standards and contractual oversight at one of Pakistan's most critical energy infrastructure sites.

What Happened on Monday

Following Monday's bund collapse, an emergency was declared at the site. Construction activities were immediately suspended and workers were directed to evacuate to safer locations. The incident triggered a sudden inrush of reservoir water, adding urgency to an already troubled project.

The Earlier Cofferdam Collapse and Its Findings

The latest incident follows a cofferdam collapse at the same project earlier in July 2025, for which Pakistan's Water and Power Development Authority (WAPDA) was held responsible, according to a report citing findings accessed by Pakistani newspaper Dawn. A three-member independent inquiry committee identified unauthorised modifications to the cofferdam design after the contract was awarded as a key contributing factor.

The committee found that all three stakeholders — the contractor, the engineer, and WAPDA — had acted outside the scope of their contractual obligations. According to the inquiry findings, PCCCL had proposed a cofferdam design alteration that was not permitted under the contract, while the supervising 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 findings specifically noted that PCCCL had proposed replacing the original cofferdam design with a rock-filled structure, considered a weaker alternative, across the project including the channel. That modified structure eventually collapsed. The inquiry also rejected attempts by stakeholders to attribute the failure to flooding, stating that water flows at the time 'were within annual levels, were not unusual and should have been taken into account in the original design.'

The Financial and Timeline Damage

The consequences of the earlier collapse have been severe. The project has been delayed by at least two years, and its estimated cost has surged by more than 285 per cent — from PKR 82.36 billion to PKR 317 billion. The inquiry attributed the failure to inadequate protective layers and filter arrangements, contradicting WAPDA's claim that flooding was responsible.

Broader Concerns Over Chinese Contractors

The Tarbela-5 project is part of Pakistan's broader energy infrastructure buildout, with significant Chinese involvement under the China-Pakistan Economic Corridor (CPEC) framework. Notably, this is the second time in rapid succession that PCCCL's work at Tarbela has come under scrutiny, raising questions about project oversight mechanisms, the role of independent engineers, and whether contractual safeguards are being enforced rigorously on Chinese-constructed infrastructure in Pakistan. Critics argue that the pattern of unauthorised design changes and regulatory approvals granted without technical scrutiny points to systemic governance gaps rather than isolated engineering failures.

What Comes Next

With construction suspended once again and a fresh emergency declared, the Tarbela-5 project faces the prospect of further delays and cost escalation. The cumulative impact of two major mishaps is likely to sharpen parliamentary and public scrutiny of WAPDA's oversight role and the contractual accountability framework governing Chinese construction firms operating in Pakistan.