Saraswati 2.0 has been building on the work conducted and results achieved in the FP7 EU India project Saraswati (Supporting consolidation, replication and up-scaling of sustainable wastewater treatment and reuse technologies for India). This project had, as first of its kind, conducted a comprehensive documentation (around 1.500 plants) and evaluation of existing decentralized wastewater treatment plants in India. It had shown that a number of decentralized wastewater treatment plants in India do not perform properly and that there are few plants that would meet the more stringent standards as those proposed by the Indian Government in 2015. Thus, in many cases not even CATNAP (the cheapest available technology narrowly avoiding prosecution) has been applied, leading to high pollution levels. The Saraswati project therefore proposed to adopt the principle of BAT (best available technologies) in a more flexible way, adapting the definition of BAT to the local context, based on complementing the treatment efficiency with the costs of the treatment technology and affordability, and local context in the location of application. This will allow to identify BATs with more stringent standards if required and suitable for the location.
Hence, the vast environmental pollution caused by untreated wastewater across India is not tackled in an efficient manner as far as decentralized wastewater treatment plants are concerned. This in turn leads to adverse environmental and health effects for society.
Saraswati 2.0 aimed at addressing this situation by identifying best available as well as affordable technologies for decentralized wastewater treatment with scope of resource/energy recovery and reuse in rural and urban areas. Thereby, initially ten pilot technologies in 7 Indian States demonstrating enhanced removal of organic pollution (BOD, TSS), nutrients (particularly Nitrogen), organic micro-pollutants and pathogens have been identified as “candidates” for best available technologies for India.
These technologies have then been piloted and their performance has been monitored and assessed. Experimental research was conducted for several pilots to optimize these pilot technologies for Indian conditions. Finally, a comprehensive sustainability assessment has been conducted, including life cycle and life costing analysis, as well as socio-economic and institutional studies. All pilots allow for resource recovery contributing to the principles of a circular economy.
Based on the results of this work, the main findings have been summarized for each pilot and it has been concluded if and to what extent, and for which circumstances to identified “candidate” technologies can be considered best available technologies for India (Deliverable 5.3).