HARIPUR (Web Desk) – Water entered the under-construction powerhouse and connecting tunnel of the Tarbela Dam Fifth Extension Hydropower Project (T-5) after a section of rock collapsed during excavation, prompting an emergency evacuation of workers and suspension of construction activities.
The incident occurred on Monday when a weak section of rock fell during excavation work on the second bench of the connecting tunnel at the T-5 project site in Haripur district.
The rockfall was followed by an inflow of water from the intake pit into the connecting tunnel and the powerhouse, creating an emergency situation at the construction site.
The Water and Power Development Authority (WAPDA) confirmed that workers were evacuated immediately after the incident. All Pakistani and foreign personnel working at the site were reported safe.
A WAPDA spokesperson said emergency measures were taken to prevent further risks to workers and protect the under-construction infrastructure.
According to the authority, water accumulated in the intake pit and subsequently entered the tunnel and powerhouse area. However, officials managed to completely drain the intake pit, while work to remove water from the powerhouse was initiated.
The spokesperson said water was no longer entering the downstream construction areas, indicating that the immediate threat of further flooding had been brought under control.
Senior WAPDA officials, project consultants and representatives of the construction contractor were examining the affected areas to determine the extent of the damage and identify the measures required to restore construction activities.
The authority also rejected reports suggesting that the project’s main Tunnel 5 had collapsed, describing such claims as incorrect.
WAPDA clarified that the main tunnel, under-construction powerhouse, tailrace culvert and switchyard had not sustained damage in the incident.
The clarification came amid concerns over the safety of the multibillion-dollar hydropower development, which is among the major ongoing energy infrastructure projects in Pakistan.
Separately, Haripur Deputy Commissioner provided details about the incident, saying that a section of the protective embankment near the T-5 project’s intake area had broken after a girder fell.
The deputy commissioner confirmed that Pakistani and foreign workers had been evacuated safely from the affected location.
He also said that a local worker who became submerged in the tunnel was rescued by people present in the area.
The incident raised concerns about construction-site safety, particularly during excavation activities involving underground structures and water intake facilities.
Sources familiar with the development said construction work at the Tarbela T-5 project had been suspended for an indefinite period following the incident.
The suspension is expected to remain in place until the affected sections are inspected and the relevant authorities determine whether conditions are safe for workers to resume their duties.
Meanwhile, WAPDA issued a separate notification concerning water discharges downstream of Tarbela Dam into the Indus River.
According to the notification, the discharge was expected to remain above 150,000 cusecs round the clock.
The authority advised all relevant departments and concerned stakeholders to make necessary precautionary arrangements in view of the increased water flow.
It also stressed the importance of ensuring public safety, particularly for communities and people living or working along the riverbanks and other potentially affected downstream areas.
Local administrations and relevant departments were urged to remain vigilant and take appropriate measures to minimise potential risks associated with the river discharge.
The latest incident has brought renewed attention to the engineering and safety challenges involved in expanding the country’s major hydropower facilities.
The Tarbela Dam, located on the Indus River in Khyber Pakhtunkhwa, is a key component of Pakistan’s water storage and electricity generation system.
The fifth extension project is intended to increase electricity generation capacity and strengthen the country’s supply of relatively low-cost hydropower.
However, the immediate priority following Monday’s incident remains the assessment of the affected construction areas, completion of dewatering operations and implementation of necessary safety measures.
WAPDA has yet to announce a timeline for the resumption of construction work or provide a final assessment of the incident’s impact on the project’s completion schedule.
Officials are expected to determine the cause of the rockfall and assess the condition of the protective structures before further excavation and construction activities can proceed.
