Abstract

Bangalore generates around 3000-4000 t/d of USW and a major constituent (72%) of which is organic waste. Today, primary and secondary collection, and transportation have been reasonably satisfactory to enable the city to remain clean. The existing solid waste treatment system in the city is not very effective. Between the 70s and 90s a significant fraction of the fermentable wastes was composted or used directly in the fields. In spite of rapid growth in USW production over the years, the capacity of compost plants has not increased. Various forms of waste recycling processes are currently functioning in Bangalore (reaching an estimated 67% of total recyclable content). This level is inadequate and it results in the production of nonfermentable wastes to be land-filled. A significant fraction of the total USW is also dumped in about 60 shifting open dump sites and poses environmental problems. The total MSW generated in Bangalore city has increased from 650 t/d (1988) to 1450 t/d (2000) and today it has become 3500 t/d. From 1988 to 2000 there is reasonable change in waste composition: fermentable, paper and plastic has increased by 7%, 3% and 0.2%, respectively. Generation rate has also increased from 0.16 (1988) to 0.58 kg/capita/day (2009) attributable to development and lifestyle changes. There is now a potential to reduce the quantity of wastes transported by adopting source segregation and facilitating decentralized treatment wherever possible. Open dumping is conducive to the generation and release of GHGs, such as methane – having 21 times more GHG potential than CO₂. As we head into a climate conscious society, it is imperative that we plan to reduce the potential GHG emissions from waste management. Our estimates indicate that there is potential for a maximum of 21.84 tCH₄/d and using IPCC default this value is estimated to be 87.32 t/d. Most components of USW incur multiple level of reuse which finally change the carbon content at each stage and offset the final dumpsite level of CO₂ and CH₄ emission estimates. No CH₄ emissions were detected at these dumpsites. A better understanding of processes and underlying factors is required to explain these findings. Conventional approaches have a limited the ability to predict C-cycle changes and resultant GHG emissions. All these pose challenges to the sustainability of Bangalore waste management system: lack of people’s participation at various stages, insufficient segregation, inadequate recycling, insufficient commercial incentives for processing fermentable and an absence of a value system for health are possible causes. The paper discusses the potential for decentralized options as possible solutions to overcome this lacuna.

Keywords: Bangalore, Municipal solid waste, Sustainability, Methane.