LAHORE, July 1: The Water and Power Development Authority plans to take the water level in Mangla lake beyond the prescribed level of 1,202 feet this year.

The exact height would be determined by the behaviour of monsoon floods and safety requirements.

Sources in Wapda claimed on Monday that a policy decision in this regard had already been taken. It could be formalized in a few days as flood predictions by the Meteorological Department matured and enabled the Authority to develop its projections of the volume of water to be handled.

Once the water level in Mangla crosses 1,90-foot mark, the control passes from the Irrigation and Power Department to the Wapda. The arrangement is meant to meet any flood contingencies which are determined by the Wapda’s flood routing plan.

The Meteorological Department has predicted above-normal rains for the coming monsoon season. However, it has not indicated the volume of water they could generate, even the volume generated by a single heavy shower.

About storing water beyond 1,202-foot level, as planned last year, the sources said it depended on the flood behaviour. The peak flood level recorded at Mangla was 1,207 feet. It was, however, reached for a very short time. The decision to sustain a high water level would of course require attention to structure safety evaluations.

About the possibility of taking the level up to 1,212 feet as planned by the Wapda last year, the sources said the Authority owned land around the lake that would allow raising the level only up to 1,210 feet.

On Monday, water level in Mangla lake level stood at 1,187.7 feet. The lake held 3.79 million acre feet water. On the corresponding day last year, the dam level was 1,145.45 feet and the storage only 1.78 MAF. If the current flows are maintained, the lake would be filled between July 10 and 15. Once the filling is complete the Wapda would have no regulatory cushion to handle unexpected rains in the catchment areas. The 12-foot margin represents about 1 MAF water.

The same margin is used for Tarbela Dam regulation once it reaches the 1,510-foot mark. The remaining 40 feet — full conservation level being 1,550 feet — is also kept for flood emergencies. The dam is then allowed to be filled by no more than a foot a day. On Monday, the Indus had an inflow of 205,700 cusecs at Tarbela and outflow of 155,000 cusecs. The dam level was 1,433.9 feet and the storage 1.67 MAF. The lake has a live capacity of 7.2 MAF.

The combined river flow touched 377,500 cusecs on Monday. This included 39,800 cusecs Jhelum inflow at Mangla — the outflow was 15,000 cusecs, 81,400 cusecs Chenab inflow at Marala and 50,600 cusecs River Kabul inflow at Nowshera.