What ails Namami Gange project

Hassle-free and affordable sewage treatment technology is the need of the hour to restore Ganga water's pristine quality

Continued inflow of untreated wastewater in the Ganga is one of the prime causes of tardy progress of the Namami Gange project to rejuvenate the country’s most revered river. Despite constantly nudging the towns around the Ganga’s banks to put up wastewater treatment plants, the bulk of the sewage generated by them is falling into the river unprocessed. High cost of setting up and operating the refining units is among the major reasons for poor interest in cleansing the dirty water before releasing it into Ganga. This handicap can be overcome to a large extent by replacing the cost-intensive and problematic conventional liquid-waste cleansing methods with the simple, hassle-free and affordable sewage treatment technology developed by the Water Technology Centre (WTC) of the New Delhi-based Indian Agricultural Research Institute.

This novel biological water purification technique uses plants and micro-organisms which possess inherent power to sequester impurities and decontaminate wastewater. It not only helps save 50 to 65 per cent of the cost but also generates revenue to make sewage treatment a profitable activity. More importantly, it requires no chemicals, no energy, no skilled manpower and no inputs, barring seeding the plants.n The perennial plant used in this system is Typha latifolia which is gifted by nature to absorb pollutants and boost oxygen content of the watery medium around its roots to cleanse the dirty water.

This plant also encourages proliferation of water decontaminating micro-organisms, thus, averting the need for using chemicals and aerators to improve water quality as is usually done in the conventional sewage treatment plants. Besides, this system removes even the metallic residues to the extent of 80 to 99 per cent — something that the conventional methods are unable to do. WTC project director Ravinder Kaur, who spearheaded the development of this technology, likens Typha plants and associated micro-organisms to kidneys to perform the vital task of eliminating impurities.

According to Kaur, the total cost of refining the untreated sewage being released into Ganga with the help of the WTC technology would come to only around Rs 1,300 crores, against over Rs 10,430 crores in the case of treatment with conventional methods. Besides, the land requirement for setting up the WTC treatment units, too, is comparatively far meagre. Moreover, these units can be transformed into environment-friendly eco-parks to woo tourists as their water bodies have been noticed to attract migratory birds. Unlike the normal sewage treatment plants which stink, the new units do not emit any unpleasant odour because the decontamination process occurs under the soil surface without the use of chemicals which generate smelly gases.

Another noteworthy feature of the new system is that, instead of producing sludge, a waste material that poses problems of proposal, the Typha-based treatment units produce biomass that can be converted into good quality particle boards or energy briquettes and pellets for use as clean fuel. The upper parts of Typha can be cut every four months or so for this purpose and the plant regenerates again.

This apart, the economic returns from the new technology based sewage treatment plants can be enhanced further by incorporating fisheries into these ventures. Planktons and zooplanktons, which serve as nutritious feed for fish, thrive well in the water ponds of these units. Experiments conducted in collaboration with a fisheries research institute have shown that the fish output of such integrated sewage treatment enterprises is relatively high and of good quality, being free of toxic residues.

Thanks to its multiple advantages and efficacy, the WTC sewage treatment technology has won the SKOCH Platinum Award — the prestigious civilian award for transformational innovation — in 2017. Earlier, the parliamentary standing committee on agriculture, convinced about its usefulness, had “strongly recommended” its nationwide application in its report presented to parliament in December 2014. The ministry of urban development, too, has issued an advisory to over 420 towns to use this technology to reclaim reusable water from sewage. It is now for the Namami Gange project to make gainful use of this technology to restore Ganga water’s pristine quality.