There are many methods to treat our most precious resource, water. What is lacking is the will to do so. Our rivers must be saved
Dusshera and Ganesh Chaturthi saw the whole country revel in festivities and devotion. However, for the water bodies in India, this was the toughest time of the year. Despite several Supreme Court and National Green Tribunal (NGT) orders pertaining to the prohibition of pollution of water bodies, many rivers are yet to experience the much-needed succor and relief. The Yamuna river in Delhi is one the many examples that continues to suffer from severe pollution throughout the year, especially during the festive seasons.
In fact, the intensity of pollution in the Yamuna has increased manifold in the last four to five years, an analysis of the Delhi Pollution Control Committee’s Yamuna water quality data revealed. The dissolved oxygen (DO) levels, for instance, which is the amount of oxygen dissolved in water, is supposed to be at a minimum of four mg/litre, but 2015 onwards has witnessed the total absence of DO in any stretch of Yamuna downstream. This even during the month of September, which being post monsoon, usually allows for better DO levels in water bodies. These conditions are a pointer of what we are doing to our rivers. As rivers passing through major cities in Indian rapidly turn into sewage drains, all hopes are now firmly attached to yet another set of interventions from the NGT. The implementation of NGT’s ‘Mailey se Nirmal Yamuna’ and laying of interceptor sewage lines along Delhi’s three biggest drains, which is likely to be completed by January 2019, will hopefully rescue the river from its current plight. Will this herald a new hope for other such polluted rivers in India, only time will tell, but in order to ensure swachhta of the rivers, treatment of polluted water is equally important to achieve desired results.
The Delhi Jal Board had submitted a draft report on sewerage management and performance of sewage treatment plants to the NGT, which revealed that at most places, the biochemical oxygen demand (BOD) — the amount of dissolved oxygen needed for micro-organisms to breakdown the organic waste in water — did not meet the standard (it should not exceed three mg/litre). Simply put, lower the BOD, the better it is for river life. On the other hand, the higher the DO, the better it is. This is where the role of sewage treatment plants (STPs) or wastewater treatment plants come in. Most STPs are either closed or working way below capacity. Out of a total of 607.06 million gallons per day of operational capacity, only 476.74 MGD sewage is treated. Even the NGT had noted that there has been a marked failure of administration in handling the situation and repeated breakdowns in carrying out binding directions of orders. These observations were made by the NGT bench headed by chairperson Adarsh Kumar Goel while evaluating the implementation of NGT’s January 2015 order on a decentralised sewerage system, where sewage falling into all drains is tapped and treated.
It is critical for the urban water bodies to be subjected to mandatory and thorough water treatment in order to prolong the life of water bodies and enable the river aquatic life to survive. To ensure this, the Government must pull out all stops towards making rivers cleaner and healthier. This in turn is possible by implementing the NGT directions and orders and by also making sure that the Central Pollution Control Board actively monitors the day-to-day quality of the river and submits periodic report to the Government and the NGT. As India hurtles towards being a more developed economy, one of the casualties has been the deteriorating state of our environment. Rapid industrialisation has, unfortunately, hiked up the number of pollutants in our surroundings. One of these pollutants is wastewater. Management of wastewater through wastewater treatment plants in India has become an imperative of our cities today. The two main sources of water contamination are sewerage and industrial waste. With the Indian population and its industrial landscape increasing at a phenomenal speed, wastewater volume is also rising at an alarming rise. Shrinking of freshwater sources, like rivers, wells, and groundwater, makes matter worse.
Before pure drinking water becomes a premium commodity, the authorities must explore various means to ensure better treatment of wastewater. The biological treatment of water is fast gaining popularity across the world. Unlike physico-chemical methods, biological treatment uses organisms to treat pollutants. Over the years, scientists have developed various aerobic or anaerobic processes to treat wastewater. This is cost-effective and efficient. Yet another successful method is the recycle and reuse method. In this method, wastewater is recycled using the membrane-based system. Membrane bioreactors use the simple science of ultrafiltration with a bioreactor to treat wastewater. This method combines physic processes with biological methods. Water treated through this can be employed for various purposes, such as irrigation.
However, the most cutting edge technology that is being employed nowadays in developed nations that Indian will do well to look at is the Zero Liquid Discharge System. This system removes all dissolved solids from the wastewater, giving us distilled water. Methods like reverse osmosis are used to purify water. Methods are many, but the will is needed to treat water before it becomes wasted water. The choice before us is very clear.
(The writer is an environmental journalist)
