ISLAMABAD, Oct 20: The Indus River System Authority (Irsa) decided here on Monday to complete the depletion of Mangla and Tarbela dams proportionately by March 15 in view of an anticipated eight per cent overall water shortage during the Rabi season, Dawn has learnt.

The decision to this effect was taken at an advisory committee meeting of Irsa, presided over by its new chairman Rahim Khan Zarkun, Irsa member representing Balochistan. Punjab member Mian Hafizullah and NWFP member Saleem Aslam also attended the meeting. The two members — one from the NWFP and the other from Punjab — will retire within a month’s time.

Sindh irrigation secretary and chief engineering adviser to the federal government represented Sindh and the Centre, respectively, in the absence of their members who retired last week.

Irsa had asked the government to let these two members continue till their replacements were made. The request, however, was not accepted.

Sources said the participants agreed to the estimates made by Irsa, without any dispute, that the overall shortage would be around eight per cent during the season. Earlier, the Sindh government was estimating zero water shortage while Irsa, Punjab and Wapda estimated it at 11 per cent, 18 per cent and 14 per cent, respectively.

The distribution of water among the provinces would continue under the existing formula, i.e., the historic use basis. The Sindh government team, comprising secretary irrigation and the irrigation consultant, did not repeat the demand for sharing of water shortages between Punjab and Sindh on equal basis.

The committee also considered anticipated water availability criteria for the Rabi season 2003-04 based on expected inflows of the Indus Basin System and the reservoir depletion criteria as projected by Irsa.

The total availability during the season had been projected at 33.565maf (million acre feet) while flows downstream Kotri were estimated at 0.150maf during the season.

As such, the total availability for Indus basin irrigation system canals would be around 33.415maf.

Total share of the NWFP and Balochistan was fixed at 1.723maf — 0.701maf for the NWFP and 1.022maf for Balochistan.

Similarly, total share of Punjab and Sindh was fixed at 31.692maf.

Punjab would get 18.065maf water during the whole Rabi season while Sindh would receive 13.627maf.

All the provinces were asked to provide to Indus river System Authority their water requirements for the whole Rabi season besides on a 10-daily basis as per crop pattern and irrigation requirements.

Pending a decision on dispute over sharing of water shortages among the provinces, water distribution to Pun-jab and Sindh is currently being made on historic use (1977-82) under a presidential directive of 2000 which favours Punjab.