Assessment of water quality and heavy metals contamination of river Ravi in Pakistan

Abstract

This study was carried out to evaluate the impact of untreated urban and industrial effluents on water quality of river Ravi. Water samples were collected from 11 polluted and relatively unpolluted sites at river Ravi during low flow season and analyzed for heavy metals content and physico-chemical parameters. Dissolved oxygen fell below the recommended limit for propagation of fish and other aquatic life as the river flows through Lahore up to Balloki Headworks. Manganese and lead contents were higher than permissible limits for aquatic ecosystems at several polluted sites of the river. Highest concentration of nickel, zinc, manganese, cadmium and lead detected in river water was 20.0 μg/L, 70.0 μg/L, 190.0 μg/L, 2.0 μg/L and 72.0 μg/L respectively. Findings revealed that river water at downstream sites of wastewater carrying drains was not suitable to support fish and other aquatic life due to its very low dissolved oxygen level.