The remaining uncollected waste poses grave public health and environmental hazards because it is left lying everywhere – in streets, market places, slums, open garbage dumps, vacant lots, on river shores. It clogs drainage systems and enters storm drains meant for rain water. There are no municipal services for collecting the waste of slum areas, where more than 30 percent of the population lives. Inadequate procedures for collection, treatment and final disposal of solid waste causes pollution of ground and drinking water, contamination of food supplies, and the spread of communicable diseases, leading to a marked deterioration in the quality of urban life.