To all Apartment ADDA community members:
Please have a look at this book entitled Self reliance in water: A practical manual for city and town dwellers" by water expert Indukanth Ragade: https://www.indiawaterportal.org/self-reliance-in-water-indukanth-ragade
This immensely valuable resource and pioneering work is a must-read for anyone who is interested in doing something about their water scarcity and quality issues, at an individual and household level. This work is based on the author Indukanth Ragade's experiences in setting up water managements systems in over 200 apartment complexes in Chennai, comprising over 4000 apartments, over a period of 20 years. The book is available for download on the above link.