ISLAMABAD: Because of a major decline in river flows, the Indus River System Authority reduced on Monday the water shares of Punjab and Sindh by 45 per cent with immediate effect, raising fears of an adverse effect on Kharif crops and a decline in power generation.

A senior official told Dawn that total flows in rivers had suddenly plunged to 119,000 cusecs from about 160,000 cusecs a week ago because of a fall in temperatures in Skardu.

The maximum temperature in Skardu, the main water source of the Indus, fell from about 25 centigrade a week ago to around 8-15 centigrade on Sunday.

As a result, the Tarbela dam hit its dead end on Sunday at 1,378 feet, falling from 1,386 feet on Friday. Therefore, discharges from Tarbela were shifted to the run-of-the-river mechanism which meant that quantities received at Tarbela are released to meet irrigation requirements.

The storage level in Mangla dam was also at a critical level of 1,093 feet, its dead level being 1,040 feet and the water regulator feared the usable quantity of water could be exhausted in a few days.

The official said the unusual drop in temperatures at this time of the season had made the river flows very unpredictable.In view of the sudden drop in flows, Irsa reduced Punjab’s share to 63,000 cusecs on Monday from 87,000 last week.

The total inflows at rim stations stood at 119,316 cusecs and the outflows at 137,000 cusecs. Likewise, Sindh’s share was slashed to 39,000 cusecs from 61,000 cusecs last week.

Balochistan and Khyber Pakhtunkhwa were exempted from water cuts because of infrastructure constraints.

The official said that since the two provinces were already getting 20 per cent cut less than their share, the total reduction in their shares had now gone up to 45 per cent.

He said all major barrages would face a major dip in their inflows and storage level over the next 8-10 days. Punjab would feel the brunt of reduced water quantities much earlier than Sindh.

The two provinces have been asked to utilise the available quantities of water efficiently to avoid a major loss to crops which were now at an early stage.

On Monday, Tarbela received a total of 35,500 cusecs while it discharged 47,700 cusecs downstream, resulting in no more storage there.

The water situation at Mangla was a little better but its storage was fast depleting. It received about 38,000 cusecs on Monday but its outflows stood at 44,000 cusecs. With this pace of discharge, the entire storage could be depleted in a few days unless a rise in temperatures or excessive rains increased the flows.

The storage level at the Chashma barrage also dropped to 638 feet on Monday against its dead level of 637 feet.

Watering is crucial to the Kharif season currently in the sowing phase. The sowing begins in April-June and the crops are harvested in October-December.

Rice, sugarcane, cotton, maize, moong, mash, bajra and juwar are some of the major Kharif crops.