IRSA expected to reassess water supply forecast for summer crops

LAHORE: Following unusual and prolonged early-summer cold waves in the catchment areas and subsequent low river flows, Indus River System Authority (IRSA) may review downward water availability forecast for early Kharif season.

According to system inflows recorded on Tuesday by the Water & Power Development Authority, an alarming trend of about 50 percent reduction in river inflows have been witnessed if compared with average flows of the last 10 years. Against the 10-year average combined system inflows of 182,800 cusecs, flow of river water was reduced to just 86,100 cusecs on Tuesday, ringing alarm bells about looming water shortage amid sowing of crucial Kharif cash crops.

If the current trend of unusually low water flows continues, it is feared that water shortage would be intensified to 15 to 18 percent against average uses instead of earlier estimated 10 percent, a senior official said.

Punjab has asked IRSA management to reassess water availability for the early Kharif season. It is expected that an in-house deliberation would soon be done to determine water availability for the early Kharif season (April 1-June 10) keeping in view persistent downward trend being witnessed in river flows.

Instead of carrying out a fresh water estimates, it is expected that IRSA, the apex water regulatory body, would adopt one of the various hydrological scenarios presented in its advisory committee meeting recently. The likely maximum and minimum water availability scenarios would be discussed along with the present inflow trend, sources said and adding anticipated shortage would be reassessed accordingly.

Dwindling water flows are feared to have negative consequences on cotton and paddy sowing, it has also cast shadow over filling of reservoirs. Tarbela dam is said to unexpectedly touch dead level in a couple of days coupled with Mangla dam witnessing an all-time low level in 10 to 15 days if present downward trend in river flows further lingered on, said sources.

The water level of Tarbela dam was 13,99.91 feet on April 27, 2021, which is just about seven feet above its minimum operating level of 1392 feet. Last year, the water level of Tarbela Day on April 27 was 1,478.48 feet.

Presently, live storage of Tarbela dam is just 0.066 million-acre feet (MAF). On the other hand, with live storage of 0.521 MAF, water level of Mangla stands at 1107.80 feet against its minimum operating level of 1050 feet. It seems that flows of the mighty Indus River have shrunken to minimal as merely inflows of 13,100 cusecs were recorded at Tarbela, against 32,700 cusecs registered on the same day last year. In sheer contrast, the corresponding average inflow of last ten stood at 38,500 cusecs, which is three times more than the flows recorded on Tuesday.

According to daily water report, the position of the river inflows and outflows at Tarbela, Mangla and Chashma along with the reservoirs levels and the barrages on Tuesday is as under:

Rivers: Indus at Tarbela: Inflows 1,3100 cusecs and Outflows 42,000 cusecs, Kabul at Nowshera: Inflows 14,000 cusecs and Outflows 14,000 cusecs, Jhelum at Mangla: Inflows 45,800 cusecs and Outflows 60,000 cusecs, Chenab at Marala: Inflows 13,200 cusecs and Outflows 4,000 cusecs.

Barrages: Jinnah: Inflows 58,000 cusecs and Outflows 52,300 cusecs, Chashma: Inflows: 49,500 cusecs and Outflows 48,000 cusecs, Taunsa: Inflows 49,000 cusecs and Outflows 44,800 cusecs, Panjnad: Inflows 22,900 cusecs and Outflows 11,900 cusecs, Guddu: Inflows 44,900 cusecs and Outflows 44,900 cusecs, Sukkur: Inflows 37,700 cusecs and Outflows 12,400 cusecs Kotri: Inflows 5,400 cusecs and Outflows 400 cusecs.

Reservoirs (Level and Storage): Tarbela: Minimum operating level 1,392 feet, present level 1399.91 feet, maximum conservation level 1,550 feet, live storage today 0.066 MAF. Mangla: Minimum operating level 1,050 feet, present level 1107.80 feet, maximum conservation level 1242 feet, live storage today 0.521 MAF.