Today, 2.1 billion people in urban areas use non-sewered (or on-site) sanitation facilities. While much of the work in rural areas is focused on creating and sustaining open defecation free communities and generating demand for communities to construct toilets, the downstream activities of collecting and transporting fecal sludge present a unique challenge for urban residents. These services are mostly provided by private operators, and are generally uncontrolled and unregulated. The inadequate disposal of fecal sludge in the environment represents a direct threat to public health and negates the positive outcomes from behavioral change and improvements in sanitation access.
The urban population in developing countries, and in particular the poor, rely on fecal sludge collection and transportation services that are often not affordable. In addition, pit emptying is often done by hand, exposing the operators to serious health risks (see figure below). Often mechanical emptiers, using vacuum trucks, charge excessive fees to customers but do not pay taxes or comply with laws and standards due to a general lack of regulation for these services. This makes it a highly profitable business. For example an emptying service provider in Abuja makes US$ 15,000 per month.