Spatial Distribution and Ecological Risk Assessment of Heavy Metals in the Basins of Dal Lake, Jammu and Kashmir

Abstract

Dal Lake, often referred to as the ‘Jewel of Kashmir’, is the second largest lake of Jammu and Kashmir and one of the most ecologically and economically important urban water bodies in the Himalayan region. Rapid urbanization, unregulated tourism, and the discharge of untreated domestic and religious-ceremony waste into its five distinct basins — Gagribal, Nigeen, Hazratbal, Bod Dal (Nishat) and Brari Nambal — have subjected the lake to sustained anthropogenic stress. This study evaluates the heavy metal load of Dal Lake across its five basins using Atomic Absorption Spectrophotometry (AAS) for seven metals: iron (Fe), nickel (Ni), lead (Pb), cadmium (Cd), chromium (Cr), copper (Cu) and manganese (Mn). Concentrations were compared against the permissible limits prescribed by the World Health Organization (WHO, 2003). The results show that, with the exception of copper, the concentrations of most heavy metals exceeded WHO permissible limits in one or more basins, with nickel, cadmium, chromium and manganese consistently elevated across all five basins. The Hazratbal, Nishat and Brari Nambal basins, which receive concentrated inputs from religious congregations, horticultural runoff and dense residential settlements respectively, showed particularly high lead and cadmium loads. The findings indicate that anthropogenic activity and unchecked urban growth around the lake periphery are the principal drivers of heavy metal contamination, and underline the urgent need for basin-specific pollution control and catchment management measures.