LAHORE, Jan 16: The Punjab irrigation department has decided to delay the opening of canals by two weeks because of fog which “supplies the required moisture to wheat crop”.

The 24 Mangla command canals, which were due to open on Jan 13, would now be made operational on Jan 31 — a day after the opening of Tarbela command canals.

This means that water would be available for the wheat crop by mid-February. The crop may get water only once as both the dams are empty by the end of February while March is largely dependent on the river flow.

Explaining the rationale behind the delay, an official of the Punjab irrigation department said that the crop did not need water urgently. The growth of crop is stunted in very low temperatures like the ones prevailing currently. Stunted growth means that plants’ biological needs are also suspended till the return of moderate temperatures, he said.

Since there is no loss of moisture at present, the department has decided to save water and utilize the extra time for clearing the canals of silt, he said. There is neither sunshine nor windy conditions, which make plants lose moisture. Therefore, a lack of water supply would not be harmful for the wheat crop.

During the rest of the Rabi season, only 52 per cent of the water required for wheat crop would be available. The Punjab made some very heavy withdrawals during the first few months of the Rabi season, which started with a 38 per cent water shortage.

The Punjab withdrew only 28 per cent of the stored water during the first half of the season to facilitate the wheat-growers. Afterwards, the department decided to make heavy withdrawals hoping that farmers would be able to use tubewell or rain water in the rest of the season. However, nothing would help those farmers who were unable to sow the crop. The province has withdrawn 9.03 million acre feet of water out of its share of 13.06maf for the season and is left with only 3.83maf for the next 75 days.

On Thursday, the two major dams of the country had only 1.543maf water with Tarbela having 1.194maf and Mangla lake only 0.349maf. The Indus supplied only 13,400 cusecs of water to Tarbela Lake, where the outflow was recorded at 15,000 cusecs. These 15,000 cusecs went to Sindh, which had started operating its canals. Water level of the lake stood at 1419.88 feet — 50.88 feet above the dead level.

The Mangla Lake dropped down to 1086.80 feet — 46.80 feet above the dead level. The lake has 0.349maf of water as against 0.784maf on the corresponding day of the last year. The inflow was recorded at 4,900 cusecs and the outflow restricted to 5,000 cusecs. River Chenab is carrying 6,470 cusecs of water while the Kabul is flowing at 5,400.

According to an office-bearer of the Farmers Associate Pakistan (FAP), the 48 per cent shortage would not hurt the crop substantially if the end of February and March were not very hot or dry.

The crop has been coping with shortage of water for the last three years and is affected by many other factors in the absence of rain. The temperature dropping down to zero degree Celsius could have been harmful had it not been so short-lived, he said.

He also pointed out that the acreage of crop had dropped down by five per cent in irrigated and 10 per cent in rain-fed areas. The reduction was caused by the delay in sugarcane-crushing season in irrigated areas, and lack of rain in Barani areas.

There might be some drop in the final yield, but it was hard to quantify the loss at this stage, he maintained.