Landslide at a major uncontrolled municipal dumpsite Case: Payatas. Quezon City, Philippines, 2000 17 In July 2000, after ten consecutive days of heavy rain, a slope of the Payatas municipal dumpsite collapsed on a slum community. The 18 hectare facility received an average of 1,500-1,800 tonnes of waste per day and was home to waste pickers who constructed their houses up to and onto the waste slope. The landslide killed nearly 300 people and left hundreds of families homeless and without a source of livelihood. The slope failure was the result of raised leachate level (due to the heavy rain, absence of soil cover and high infiltration), landfill gas pressures, low waste density (due to limited compaction) and unstable slopes at too acute an angle.18 Although the dumpsite was closed in the aftermath of the tragedy, the impact on the cleanliness of the city forced local authorities to re-open it in November.
© Merry et al.
In 2001 the City government started work to transform the dumpsite into a controlled waste disposal facility and an eco-park. Work on the site included slope re-profiling and terracing, stabilization and greening, leachate collection and recirculation, drainage system improvement, fortified roadways and access to the site, gas venting and material recovery. In 2004 a 110kW Pilot Methane Power plant was set up at the site and in 2007/8 a Biogas Emissions Reduction Project started. The project was the first Clean Development Mechanism (CDM) project in solid waste management in the Philippines and in Southeast Asia and registered under the Kyoto Protocol of the United Nations Framework Convention on Climate Change (UNFCCC). GHG emissions have been reduced by an estimated 116,000 tonnes CO 2 per annum. In addition, employment has been created, local capacity of the technology and know-how have been cultivated and financial resources from the sale of Certified Emission Reductions, or carbon credits, have been obtained. The project is considered a showcase of best practices.
Photo courtesy: Luis Sabater
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The Payatas Dumpsite: From Tragedy to Triumph – http://www.quezoncity.gov.ph/index.php?option=com_content&id=207%3Athe-payatas-dumpsite-fromtragedy-totriumph&Itemid=235&showall=1 Based on an analysis carried out by Kavazanjian, E., S. Merry, and colleagues. See http://faculty.engineering.asu.edu/kavazanjian/wp-content/ uploads/2011/07/17_Merry-et-al-ASCE-Payatas.pdf and http://casehistories.geoengineer.org/volume/volume2/issue3/IJGCH_2_3_3.pdf
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