Safdar Ali Safdar
Gilgit: A recent research study has revealed that most of the drinking water sources in Gilgit-Baltistan are contaminated with heavy metals, which are attributed to the natural geogenic processes taking place in the region. These metals are potential environmental contaminants and hazardous to human health.
The research was jointly conducted by experts from the Gilgit-Baltistan Environmetal Protection Agency (GB-EPA) and the Department of Environmental Sciences and Plant Sciences of Karakorum International University (KIU) including Syed Waqar Hussain, Khadim Hussain, Qandeel Zehra, Samreen Liaqat, Ajaz Ali, Yawar Abbas and Babar Hussain.
The study was carried out to investigate “the quantification of heavy metals in selected springs and surface drinking water sources of Gilgit-Baltistan”. For this purpose, a total of 66 water samples were collected and analysed. The concentration of heavy metals in 20% of the samples was beyond the National Standards for Drinking Water Quality (NSDWQ) and WHO guidelines. The concentration of heavy metals in 59% of the samples were within the permissible limits and only 21% of samples were free of heavy metals. The highest concentration of heavy metal beyond the permissible limit of NSDWQ was found in Skardu (23%), Nagar (15%), Hunza (15%) and 8% in Gilgit, Diamer and Ghizer respectively.
The study discusses that access to water is not an issue in GB. However quality of water has always been a concern in the region. Rapid population growth, economic advances, anthropogenic activities, lack of planning, capacities, and financial resources along with climate change are the fundamental factors for deterioration of water quality in GB.
The study states that springs, rivers and streams are the three main sources of drinking water in GB while surface water is the main source of water supply in urban areas of Gilgit-Baltistan. Usage of groundwater for domestic water supply is not common except in the low lying settlements of Gilgit city and a few riverside villages in Skardu, where people draw water from shallow wells. Quantity of water supply reduces in winter season due to reduced glacial melt in most of the urban areas. Humans get exposed to heavy metals (HM) through inhalation and ingestion; long lasting bioaccumulation and toxicity of heavy metals (HM) have been found to be highly hazardous to human health and ecosystem.
The study says that presence of these chemicals in springs and surface water sources are the main cause of the health issues in the region. Water supply is a specialized subject of Public Health Engineering being dealt in the region through conventional methods and practices. A water supply system in GB is meant to take water from the source and store in a tank for subsequent supply to the command area without any treatment, keeping in view the water quality and its demand for making it safe.
The treatment system to remove chemical contamination from drinking water is highly technical and expensive. It is better option to avoid the source contaminated with chemicals.
The study recommends that the future planning of water supply systems in GB shall be considered the nature and concentration of the pollutants in the water source and provision of appropriate treatment system.