Greywater refers to the wastewater generated from cooking, bathing, washing hands and washing clothes. While this water is not potable, treated greywater can be utilised for certain activities, such as watering plants and flushing toilets. In recent years, nature-based greywater treatment systems have gained popularity as a sustainable solution to address freshwater scarcity and water quality degradation. These systems use natural processes to treat and recycle greywater, providing a cost-effective, decentralised and eco-friendly alternative to traditional treatment methods. The key features of these systems include biofiltration units, constructed wetlands and natural filters. While greywater treatments can improve water reuse and water quality in schools, there is a paucity of literature on their treatment efficacy in schools across the Global South.

To address this gap in literature, a review of the available technical literature and ATREE’s past water quality work will be combined with a survey of wastewater generation and treatment from 25 government schools across Bangalore. Through the survey, school-level data will be collected on water sources and discharge points, status of water and sanitation infrastructure, operations and maintenance-related activities and the costs associated with water and sanitation infrastructure and activities. Additionally, water and wastewater samples will be collected from the schools and tested for quality parameters such as BOD, COD, phosphate, nitrate and fecal coliform. Through this exercise, the overarching goal is to create a web-based tool that can help policymakers, NGOs and other stakeholders identify the most appropriate wastewater treatment system for individual schools.