The country continues to lose its water storage capacity as accumulation of silt has decreased Tarbela Dam’s storage space by another two feet.
An official of the ministry of water and power told the media that the dead storage level of the dam had been increased to 1,380 feet from 1,378 feet a few days ago because of the rising level of silt. As a result, the storage capacity of the dam has decreased by two feet.
“There is no economically viable option to stop loss of storage capacity at Tarbela except to build dams in the upstream to reduce the amount of silt reaching one of the two major reservoirs of the country.”
He said the change in the storage parameters had been made on the recommendations of the Water and Power Development Authority (Wapda) on the basis of annual analysis of various factors relating to the dam. Wapda’s technical team on dams had recommended an increase of four feet in the dead level but the change was kept at two feet to avoid a drastic cut in discharges.
He said the country’s live water storage capacity had dropped by about 30 per cent despite an addition of about 2.9 million acre feet (MAF) capacity through Mangla dam upraising project.
The official said Tarbela alone had lost about 35 per cent of its designed capacity of about 9.7 MAF which had come to 6.2 MAF.
