Decentralized Wastewater Treatment Systems (DEWATs) have been successfully implemented in various parts of India to treat wastewater locally. In Auroville, Tamil Nadu, DEWATs are used in residential communities and institutions to clean wastewater naturally and reuse it. Similarly, in Dharavi, Mumbai, one of the most densely populated areas, DEWATs have helped reduce the amount of untreated sewage flowing into local drains. In Bodh Gaya, Bihar, hotels and monasteries have adopted this system to prevent polluted water from entering the Falgu River. Additionally, this technology has played a key role in restoring Sarakki and Jakkur lakes in Bangalore, reducing pollution and reviving aquatic life.
In Delhi, the Yamuna River faces severe pollution due to untreated sewage. Large drains like Najafgarh, Shahdara, and Barapullah discharge nearly 80% of untreated wastewater directly into the river. DEWATs can be a practical solution by treating sewage at the source, especially in slums, public toilets, markets, and residential complexes. These systems require low maintenance, work without electricity, and use natural processes to remove organic and chemical waste. By implementing DEWATs in key locations, the Biochemical Oxygen Demand (BOD) in the Yamuna can be reduced, while Dissolved Oxygen (DO) can be increased, helping restore aquatic ecosystems.
If DEWATs are adopted on a large scale in Delhi, they can significantly improve the health of the Yamuna. This system is cost-effective, sustainable, and community-friendly, making it a practical approach to tackling water pollution. By preventing untreated sewage from entering the river, Delhi can take a major step toward reviving the Yamuna, making it cleaner and healthier for future generations.
