ANNOUNCEMENTS
The Kodaganar River originates from the eastern slopes of the Palani Hills, flows through the town of Vedasandur in Dindigul district, Tamil Nadu, India, before joining the Kaveri River. Although a greywater drainage system was constructed in Vedasandur in the early 2000s, the absence of a wastewater treatment facility has led to the direct discharge of untreated greywater into the river through 22 drain end points (DEPs).
This study assesses the water quality in the Kodaganar River and the wastewater that is discharged into it by analysing key water quality parameters, including pH, dissolved oxygen (DO), biochemical oxygen demand over three days (BOD₃), chemical oxygen demand (COD), faecal coliforms, total suspended solids (TSS), nitrate-nitrogen (NO₃-N), electrical conductivity, total alkalinity, phosphorus and chloride. Longitudinal sampling was conducted at eight strategic locations along the river - upstream, within Vedasandur, and downstream (including the inlet and outlet of the Alagapuri Dam). Wastewater samples were collected from the 11 drain endpoints (DEPs) that have significant flow and discharge directly into the river.
The results revealed critically low DO levels downstream (as low as 0.7 mg/l), high faecal coliform concentrations (up to 108,000 CFU/100 ml), and sustained ionic pollution through the town stretch. A QUAL2Kw model was developed and calibrated (with a fitness of 0.9036) to simulate pollutant dynamics, revealing the limited self-purification capacity of the river and the compounding role of the Alagapuri Dam in trapping pollutants.
The study highlights the urgent need for decentralised wastewater treatment, strengthened sanitation infrastructure, and a dedicated river management authority. QUAL2Kw proved to be a valuable tool for simulating pollution impacts, though its application remains limited without further validation.
Keywords: Greywater, River Pollution, Water Quality Assessment, QUAL2Kw Modelling, Wastewater Management.
