HARIPUR: A section of the protective bund at the intake of the Tarbela 5th Extension hydropower project gave way on Monday, sending water into Tunnel Five and the under-construction powerhouse and halting work on one of Pakistan’s biggest power projects for an indefinite period. Every worker at the site, Pakistani and foreign, was evacuated safely, and no casualties were reported, officials said.
The Water and Power Development Authority (WAPDA) said the inflow began during excavation of the second bench connecting tunnel, when a weak mass of rock collapsed and water from the intake pit entered the tunnel and the powerhouse area. “The water from the Intake Pit has been completely drained, and no further water is entering the downstream work sites,” the authority said, adding that dewatering of the under-construction powerhouse had begun.
Haripur Deputy Commissioner Waseem Ahmed, who visited the site, said the situation was fully under control. Only one section of the project collapsed, he said, a WAPDA technical team and Haripur police were monitoring the site, and nearby communities faced no danger. One local worker who was submerged as the tunnel filled was pulled out alive by local people, Ahmed said.
Two accounts of what failed first
The first official word pointed to a different cause. In his initial statement, Ahmed said a girder fell at the T5 project intake, breaking part of the protective embankment and letting water into Tunnel Five. WAPDA’s later statement attributed the inflow to the rock collapse during excavation. Neither account has been settled. Ahmed said a high-level inquiry would examine whether a structural weakness or a technical fault caused the bund to fail, and that the next course of action would be decided after the inquiry report.
WAPDA rejected reports circulating that the main T-5 tunnel had collapsed, saying the main tunnel, the under-construction powerhouse, the tailrace culvert and the switchyard had suffered no damage. Senior WAPDA officers, the project engineer and the contractor were assessing the situation, the authority said.
A project already behind schedule
The T-5 project is being built at Tunnel No 5 of Tarbela Dam. It is designed to add 1,530 megawatts through three generating units of 510 megawatts each, lifting Tarbela’s installed capacity from 4,888 megawatts to 6,418 megawatts and adding about 1.466 billion units of low cost electricity a year, according to WAPDA. The project’s approved cost is $807 million, with the World Bank providing $390 million and the Asian Infrastructure Investment Bank $300 million. WAPDA awarded the civil works contract to China’s Power Construction Corporation in May 2021 at $354.6 million.
WAPDA said in January that the project was 56 percent complete and that its first unit was scheduled to start generating electricity in April 2027. The overall completion date has since slipped to September 2027. WAPDA has not said what Monday’s flooding will cost, or whether that date will move again.
This is the second time in about 15 months that water has interrupted work at T-5. In August 2025, work was temporarily suspended after rising reservoir levels sent water into the construction site. A government inquiry into an earlier cofferdam collapse at the project, whose findings were reported in July, held the contractor, the consultant and WAPDA responsible, citing unauthorized design changes made after the contract was signed, among them an unapproved switch from roller compacted concrete to a rock fill structure.
For Pakistan’s power sector, the open question is how long T-5 stays offline. The project is meant to add cheap hydropower to a grid that relies heavily on imported fuel, and every further delay pushes that relief back. Until the inquiry reports, there is no date for work to restart.
Read this story in Urdu: زرک نیوز اردو
Reporting based on statements by WAPDA and the Haripur district administration, as reported by Radio Pakistan, Dawn, The Express Tribune, The News and Pakistan Point.
