Chandigarh: Despite the regulatory end of Sukhna Lake drying up early this summer and the India Meteorological Department forecasting below-normal rainfall this year, Chandigarh administration officials have allayed fears of the main lake body drying up.Concerns had been raised over the possibility of the lake, or parts of it, going dry. Acting on these, teams from the UT engineering and forest depts have conducted multiple inspections of the water body. After the latest inspection on Wednesday, officials said the risk remains minimal.UT chief engineer C B Ojha, who was part of the team that made inspections of the lake, said, “The water level at present is similar to levels in the last few years wherein no drying up of the lake was witnessed.”On the regulatory end drying up so early in the summer season, Ojha said, “The regulatory end is not part of the main lake, but is connected to the Sukhna choe.”In the seven-eight months since the monsoon last year, the water level has dropped by more than four feet in the lake and continues to decline. Last year, because of heavy rains, the flood gates at the regulatory were opened more than 10 times after the water level breached the danger mark.“At this rate, we are expecting the water level to further dip by at least 3-4 feet and stabilise around the 1,156 ft mark. But this depends on the intensity of the heat in the coming days,” said a senior UT official who didn’t wish to be named.It is nearly a decade since the lake or major parts of it dried up. It was in 2017 when large patches of dry land could be seen in the lake. Similarly, the lake dried up in 2012 and 2010.Along with seasonal factors like high summer temperatures and poor rainfall, a perennial issue affecting the lake’s prospects of drying up is it losing its water storage capacity.The lake’s storage capacity has seen dramatic changes over the decades due to heavy siltation from the Shivalik catchment. At its inception in 1958, the capacity stood at 1,074 hectare-metres (Ham). It plummeted to a low of 343 Ham by 1999 before recovering to 545 Ham by 2015 — still only about half of its original volume.The Chandigarh administration last year engaged the National Institute of Hydrology (NIH), Roorkee, for integrated hydrological investigations. The NIH initial findings identified the regulatory end as a potential zone for increasing storage capacity through targeted interventions.Based on these recommendations, authorities are exploring ways to enhance the lake’s water-holding ability while addressing ongoing silt accumulation.Ojha said, “The desiltation will be taken up as required. Though, at present, even at the dried-up regulatory end, the soil is still very soggy. It is not possible to take heavy digging machinery to the site. Plans are being finalised for the desiltation to be carried out as and when the conditions are right.”BOX1: OVERALL SUKHNA WATER LEVELS ON April 22 Year | Water level (in ft)* 2023 | 1158.65 2024 | 1158.10 2025 | 1157.70 2026 | 1158.40 *Source: UT Engineering department BOX2: WATER STORAGE CAPACITY Apart from heat and rainfall patterns, heavy siltation has reduced the lake’s storage capacity over decadesYear | Storage capacity (hectare-metres – HAM)1958 | 1074 1963 | 709 1976 | 338 1988 | 354 1999 | 343 2001 | 356 2002 | 513 2011 | 524 2012 | 532 2015 | 545Large portions of the lake last dried up in 2017, with similar situations reported in 2012 and 2010.
