Below Kotri water releases exceed storage capacity of 3 dams

ISLAMABAD: The below Kotri water releases to keep Sindh’s fertile land safe from sea intrusion in five months of ongoing Kharif season have reached 11.6 million acres feet (MAF), a figure that has virtually exceeded the stored water of 11.506 MAF in Tarbela, Mangla and Chashma reservoirs, the water flows data shows.

The positive aspect of the development is that the current cumulative water storage is 2pc higher than the five-year average of 11.267 MAF, meaning that the country would be having a sizeable water carryover for Rabi crops. The country is at present rich with water inflows of 296,100 cusecs, with outflows of 281,500 cusecs.

The Indus River System Authority (IRSA) is bound to release in the whole year at least 10 MAF of water downstream Kotri to halt the sea intrusion. When water releases below Kotri are reduced in the wake of low inflows in rivers and dams, then sea water not only intrudes into the land of the low riparian Sindh but also damages the coastal land with heavy water salt turning it into infertile one. According to estimates worked out by water experts, nearly 3.5 million acres of agricultural land in Sindh has been eroded since 1956 because of the sea intrusion.

However, the water regulator has so far released water of 11.6 MAF into the sea just in five months, from April 1 to August 29, 2024. Since the mighty India is fully charged with water flows and Tarbela Dam is brimming up to the optimum level of 1,550ft and more importantly, Kabul river is also showing its might with maximum flows, the regulator is left with no option but to release the water into the sea. “If we had more reservoirs on the Indus, the water regulator could have managed to accumulate more quantity of water and ensure the regulated below Kotri water releases in 12 months of the year,” a senior official at the Water Resources Ministry told The News.

“Tarbela at the Indus has now come on the run of the river as inflows and outflows are now the same at 183,000 cusecs. All federating units are being provided indented water supplies from Indus and Chenab Zone: Punjab is getting 116,100 cusecs, while Sindh is being provided 180,000 cusecs, Balochistan 12,000 cusecs and KP is absorbing 2,200 cusecs per day.”

As per water flows data as of August 29, 2024, the water level in Chashma reservoir also stands at 648.50 feet, close to its maximum conservation level of 649 feet, while Mangla reservoir is filled to 1,217.90 feet, slightly above the five years average of 1,217.45 feet, with a storage of 5.455 MAF, slightly more than the five years average of 5.423 MAF.

The Mangla Reservoir level is expected to improve further due to reduced irrigation demand, driven by forecast of rainfall in the southern regions of the country and improved flows in the Indus and Kabul rivers.

If the current trends of inflows in the Jhelum River and releases from the reservoir continue through September 10, Mangla is likely to attain the level of 1,222 feet, with the potential for further improvement depending on the hydrological response of the Chenab River and rainfall in the Mangla Dam catchment area.

At Marala, water inflows in Chenab subsided to 47,800 cusecs while the outflows stood at 18,800 cusecs.