Sewage Sludge Scenario in India It’s Treatment & Management

With rapid population growth and infrastructure development, sewerage networks are expanding, connecting more households and increasing wastewater volumes. Approximately 80% of the water supplied becomes wastewater. While a portion is treated in wastewater treatment plants (WWTPs), a significant amount is discharged into natural water bodies, causing pollution. Although policies for wastewater treatment exist and are evolving, sludge—a by-product of treatment—poses a disposal challenge. Despite making up a small fraction of the treated wastewater, sludge contains heavy metals, pathogens, organic pollutants, and decomposable matter. However, it also holds reusable nutrients and organics, prompting the need for sustainable and economical reuse methods. Traditionally viewed as waste, sludge was not accurately quantified in the past. Today, limited land availability and growing sludge volumes make its disposal a critical issue, highlighting the importance of proper management based on potential applications. India currently lacks a dedicated policy for sludge management, though efforts are underway to address it in upcoming WWTPs and to develop solutions for existing facilities. This thesis assesses the estimated sludge generation from Indian STPs/WWTPs, its treatment by municipal bodies, and global best practices. It includes a case study on Delhi and Mumbai, evaluating sludge quantities, disposal techniques, and associated challenges.