by Welthungerhilfe, Institute of Water and Sanitation Development, IRC, Green-Earth Waste Management Services


In Zimbabwe, high population growth and limited space in peri-urban centres, coupled with fiscal constraints on the provision of reticulated sewerage systems, mean that existing pit latrines must be de-sludged. However, the country currently has no appropriate technology for emptying latrines in dense settlements.

The Research into Sludge Enterprise (RISE) initiative trialled the viability and applicability of mobile de-sludging units (MDUs) in pilot locations including Norton, a township near Harare.

Overall, households report that the MDU service is a quick, hygienic and efficient way to
de-sludge tanks and pits, despite concerns about costs and the limited capacity of the holding tank. Lessons from the pilot include the need for the service to focus on its niche market (pit latrines) in households in high density areas and also institutions such as schools and clinics for improved business viability. Business mentorship was crucial to the successful operation of the MDU. Systematic customer feedback is important, as is ongoing, targeted marketing, capital financing mechanisms and regulatory enforcement.

The adaptation and application of the Technology Applicability Framework (TAF) and
Technology Introduction Process (TIP) as action research tools through each phase of the pilot built skills, relationships, expedited progress and performance, helped identify actions to address bottlenecks, and systematised the research data.