Delivering clean water to vulnerable communities on the Ganga The PAVITRA GANGA team is piloting advanced technologies to treat and recycle water, benefiting communities in the Ganga River Basin. The systems are helping to protect local water sources from pollutants from tanneries, hospitals and industry. Climate Change and Environment © Vinod Khapekar/stock.adobe.com The Ganga River is a sacred water source that flows east from the Himalayas through India and into Bangladesh. It is a critical component of India’s economy and important for public health. Yet it suffers from high pollution and contamination by heavy metals. The PAVITRA GANGA project is co-funded by the EU and India’s Department of Science and Technology. A collaborative team of Indian and European researchers are testing a range of advanced technologies to offer waste water treatment to communities who lack adequate access. “The PAVITRA GANGA project aims to explore the opportunities for low-cost and energy-efficient solutions for waste water treatment, reuse and resources recovery in peri-urban India,” says Jaiswal Anshuman, director of the Water Resources Division at The Energy and Resources Institute (TERI). Paul Campling, international business development manager at the Flemish Institute for Technological Research (VITO) and PAVITRA GANGA project coordinator, explains that the project focuses on two distinct urban and peri-urban waste water treatment cases typical for India. The first is at an urban waste water treatment plant in Kanpur, on the banks of the Ganga River, which has been impacted by illegal discharges of tannery waste water into the sewage system. The second is an open drain in New Delhi, which is meant to remove excess rainfall during the monsoons but is likewise impacted by illegal discharges of industrial and hospital waste water. “In both cases, socially vulnerable groups are using the partially treated waste water for irrigation and non-potable uses, which is detrimental to their health and well-being,” adds Campling. Exploring new treatment technologies PAVITRA GANGA focuses on two types of treatment technologies. The first remove bulk organic material and nutrients, and the second, known as polishing technologies, remove contaminants of emerging concern such as pharmaceuticals and heavy metals. One of the technologies trialled, a self-forming dynamic membrane bioreactor (SFD-MBR), separates solids and liquids through a self-forming cake layer on the surface. The team has shown this method offers improvements over conventional filtration systems. Another is the ANDICOS modular system that can be added to existing treatment plants, filtering waste water through membranes to produce a sewage concentrate. This concentrate can be mixed with other organic waste streams to produce biogas and, eventually, electricity. The team are testing additional treatment technologies, including constructed wetlands and structured adsorbents to remove pharmaceutical residues, and low-cost approaches for open drains, such as a photoactivated sludge (PAS) system that uses algae to remove pollutants. “We are also working with the local population to improve awareness of the fact that it is more prudent to prevent waste water reaching open drains in the first place,” notes Campling. Proving technology in real-world pilots All technologies studied by PAVITRA GANGA are first tested in the laboratory before being upscaled to demonstrate pilots under real-world conditions, with the collaboration of local scientists. In total, the project is running eight pilots, some of which have been more successful than others. One issue has been the dramatic changes in the waste water quality before and after COVID-19, pushing beyond the design parameters of pilots based on previous water quality characteristics. Nonetheless, Campling remarks: “The filtration-based pilots have worked extremely well considering the changing water characteristics.” There are ongoing discussions to implement successful technologies at other locations after the project funding ends. The team is also providing capacity-building workshops and online course material for Indian water professionals, through the establishment of a technology and learning network. “The experience of working in collaboration with Indian researchers has been very rewarding,” says Campling, “with a lot of interactions on how to design laboratory experiments to support real-world piloting.” Anshuman concludes: “The project partners’ joint interventions bring significant learnings and insights for co-creating options for better water governance and policy interventions.” Keywords PAVITRA GANGA, India, Ganga River, water, treatment, technologies, contaminants, polishing, reactor, sludge, algae
