Analysis of Independent Faecal Sludge Treatment Plants in West Bengal, India towards Sustainable Faecal Waste Management

60 percent of toilets in India are constructed with an onsite sanitation system (OSS). In the West Bengal (WB) State of India, 78 percent of the urban population is covered with unsewered and OSS systems. There is no detailed study that compares the economic benefits of FSTP in India with those of a Sewerage Treatment Plant (STP). This study is done to derive the anticipated outcome and benefits which may be achieved from independent Faecal Sludge Treatment Plants (FSTP) concerning economic aspects and control of environmental pollution caused by untreated discharge of Faecal Sludge (FS) and Septage into open ground and water bodies. The study was conducted in an indigenous and unique manner, following rigorous literature reviews and data collection. The study emphasises the immediate implementation of FSTP in each city where an unserved sanitation system exists. To establish an independent FSTP with 100 KLD capacity, it is concluded that the average capital cost (CapEx) for construction and its operation and maintenance cost (OpEx) for 15 years are around INR 106.5 million and INR 330 million, respectively. Considering this, the total CapEx plus OpEx (15 years) incurs around INR 985 per capita for using FSTP. On the other hand, the same approach, using STP, amounts to approximately INR 18,000 per capita, comprising capital expenditure (INR 9,000) and Operational Expenditure (INR 9,000 for 15 years). The economic benefits of adopting FSTP over STP are expected to reach INR 251 billion within the first 15 years. Moreover, end products of FSTPs add resource recovery, control environmental pollution, ensure sustainable development goals and promote a circular economy.