Assessment of the Impact of Urbanization on the Water Quality of Kalundre River, Maharashtra, India

Abstract

Background: Rivers are essential freshwater resources, although increasing urbanisation and industrial activities have led to significant water quality degradation. The Kalundre River in Panvel, Maharashtra, India, flows through diverse land-use areas, including residential, agricultural, and urban zones, making it susceptible to pollution from domestic sewage, industrial effluents, and urban runoff. Aim: This study examined physicochemical conditions along the Kalundre River, Maharashtra, at four sampling sites representing different levels of human influence. Methods: A cross-sectional observational study was conducted at four sampling sites along the river, representing upstream (minimal impact), midstream (moderate impact), and downstream (high urban/industrial influence). Water samples were collected at a depth of 20–30 cm using sterilized bottles and analysed according to APHA standard methods. Parameters measured included pH, electrical conductivity (EC), total dissolved solids (TDS), dissolved oxygen (DO), biological oxygen demand (BOD), chemical oxygen demand (COD), alkalinity, and major ions (Ca²⁺, Mg²⁺, Na⁺, K⁺, HCO₃⁻, Cl⁻, SO₄²⁻). Results: Water quality deteriorated progressively from upstream (S1) to downstream (S4). EC, TDS, BOD, COD, and major ions increased, while DO decreased, indicating elevated organic and chemical pollution. Upstream S1 showed good water quality, S2 was moderately polluted due to domestic discharge, and S3–S4 exhibited poor to very poor conditions influenced by urban sewage and industrial effluents. Major ions, such as Cl⁻ and SO₄²⁻ highlighted anthropogenic contributions from sewage and industrial sources. Conclusion: The study demonstrates the strong impact of urbanisation and industrialisation on river water quality. The downstream degradation emphasises the need for effective wastewater management, pollution control, and sustainable water resource management to protect river ecosystems.