Islamabad, Nov 10 : A breach in a protective embankment at the Tarbela Dam's Tunnel Five hydropower project in Pakistan's Khyber Pakhtunkhwa province triggered a flood with officials stopping the construction work due to the collapse of protective embankment, local media reported. The project reportedly involves Chinese construction firms.
The breach of protective embankment caused an increased flow of water in the River Indus, with authorities issuing an alert for the regions near the river, Pakistan-based daily 'The Express Tribune' reported.
A weak rock mass collapsed during excavation of the second bench connecting tunnel, causing water from the intake pit to enter the tunnel and the powerhouse area, according to a statement issued by the Water and Power Development Authority (Wapda).
The statement said, "The water from the Intake Pit has been completely drained, and no further water is entering the downstream work sites," adding that dewatering from the under-construction powerhouse had began.
No casualties were reported as all workers were immediately evacuated after the incident. Wapda said that senior officers, the engineer and the contractor were analysing the situation to address any challenges to the T-5 project, The Express Tribune reported.
Tarbella Dam authorities said that the inflow of water in the River Indus was expected to reach 150,000 cusecs in the next 24 hours. It ordered all relevant department, district administrations and the public to take precautionary measures due to possible risks. It urged people to avoid going near the banks of the River Indus and to refrain from bathing, swimming or boating in the river.
Haripur Deputy Commissioner Waseem Ahmed said that water had entered the tunnel after the protective embankment collapsed. He said that one Pakistan worker was swept into the water as the tunnel flooded but they were rescued by emergency teams, adding that no casualties had been reported. He said that construction work on the T-5 project had been suspended indefinitely after the incident, while a probe has been launched to determine the cause of the breach.
The construction work was part of the Tarbela 5th Extension Hydropower Project and was planned to add 1,530 megawatts to the dam's installed generation capacity through three units of 510MW each, The Express Tribune reported.
After its completion, the project was expected to generate an average of 1.347 billion units of electricity annually and increase Tarbela Dam's installed capacity from 4,888MW to 6,418MW. The project has been delayed repeatedly, pushing its completion deadline back from the original five-year schedule to September 2027.
