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Climate Smart Agriculture Sourcebook

Developing Sustainable Food Systems and Value Chains for Climate-Smart Agriculture

Production and Resources

Case Study 10.1 Valorization of food waste for developing sustainable food value chains: Composting urban waste into agricultural inputs, Balangoda Urban Council, Sri Lanka

According to the European Commission’s Emissions Database for Global Atmospheric Research, global food loss and waste generates 4.4 gigatonnes of carbon dioxide equivalent annually, or about 8 percent of total anthropogenic greenhouse gas emissions (EC, 2012; FAO, 2015). Minimizing or preventing food loss and waste at the source, as well as reusing safe and nutritious food waste as human food or for high-value non-food consumption (e.g. as animal feed, fertilizer or biomass), would reduce the negative economic and environmental impacts of food loss and waste.

In Sri Lanka, much of the solid waste is openly dumped into waterways and vacant fields in populated areas. Generally, municipal waste collection services are insufficient and only cover the urbanized and commercial areas of cities and towns. Most of the waste that is collected in Sri Lanka ends up in landfill sites, which are usually located close to streams, marshes or forested areas and can harm the environment and public health.  

The Balangoda Urban Council in Sri Lanka is one of the oldest local administrations, dating back to 1939. As with many other cities, solid waste management was a key issue for the Balangoda Urban Council. Waste accumulation in the city caused many problems, including unpleasant odours, contamination of water bodies and paddy fields, and gave rise to diseases such as Salmonella, typhoid fever, and diarrhoea. The main objective of the present administration is to build a green and environmentally friendly city by 2025, which includes a waste management project.

Although the composition of municipal solid waste (MSW) in Sri Lanka has a high proportion of organic matter, it also has a high moisture content at about 60 to 75 percent, and a low calorific value at about 1000 to 1200 kilocalorie per kilogram. Due to the low calorific value and high moisture content, the MSW composition is not viable for incineration for energy production. However, MSW with a high organic and moisture content has great potential for composting.

Like many other small- and medium-sized cities in Sri Lanka, Balangoda has introduced a compost plant – with government funding support – to recycle organic waste and produce compost for use in peri-urban and rural agriculture. Most of the compost plants have been established in peri-urban or rural areas, which facilitates the reuse of the compost produced in nearby agricultural areas. 

In Balangoda, total MSW collection stands at 20 tonnes per day, with a 100 percent collection coverage. The garbage collected by the urban council is divided into non-degradable garbage (e.g. plastic and glass), which is sold, and non-degradable garbage, which is used to make compost. The compost plant project was initiated in 1999 as a city service to provide a solution to the solid waste management problem, but converted into a business later. Integrated waste management in Balangoda now consists of an MSW compost plant, a septage treatment plant, plastic pelletizer and an open dumping ground. The Balangoda Composting Plant recycles MSW, faecal sludge, fish waste, and slaughterhouse waste, with a capacity of 14 tonnes per day. In 2005, a waste-purchasing centre was built with support from the municipality to buy non-degradable waste from the city. In 2008, a night soil (i.e. human excrement that is collected at night from cesspools for use as manure) treatment plant was established. The current revenue stream of the plant is now made up by the sale of the compost from MSW and 'super compost' from the night soil. The quantity of organic fertilizer produced by the plant has increased from 2 620 kilograms in 2003 to 385 660 kilograms in 2009. Income generated in 2009 from fertilizer sales (1 345 660 Sri Lankan Rupees) was over 100 times the income generated in 2003 (13 100 Sri Lankan Rupees). The income collected by selling recyclable goods in 2003 was 75 450 Sri Lankan Rupees and increased in 2009 to 432 650 Sri Lankan Rupees (Cofie and Jackson, 2013). 

City dwellers benefit from the improved waste management system and reduced health risks by reducing direct contact with untreated waste in informal dumping sites. Farmers around Balangoda benefit from the production of organic fertilizers. This recycling of urban waste resources to benefit peri-urban and rural agriculture constitutes an effective strategy for operationalizing urban-rural linkages. The plant brings additional income to the municipality and the economic benefits are shared between the municipality and the seventeen plant workers. 

In spite of the increased sales of compost, the compost produced by the project is not competitive with chemical fertilizers, which are heavily subsidized. A 50 kilogram bag of chemical fertilizer at the subsidised rate is cheaper than a 50 kilogram bag of the compost. As chemical fertilizers have a higher concentration of essential plant nutrients, the chemical fertilizer can be applied in smaller quantities than compost. The comparative advantage of the compost produced by the Balangoda plant lies in its ability to improve the quality of the soil, which is particularly important given the sandy soils in the province. Chemical fertilizers leach out of the soil without a soil conditioner, such as compost. Awareness raising and training to educate the public and farmers on the benefits of integrated waste management and the use of compost are indispensable for improving the uptake of this sort of initiative. 

Source: GIZ, FAO and RUAF, 2016