Faecal Sludge Management in Lusaka, Zambia

Authors: Alison Parker, Peter Cruddas and Chris Rose, Cranfield University

This case study examines issues surrounding the management of faecal sludge, using Lusaka in Zambia as a case example. 2.5 billion people on our planet still lack access to improved sanitation – they have nowhere safe to go to the toilet (WHO and UNICEF 2014). Instead, they defecate in the open, use a “flying toilet” (a plastic bag which is thrown away), or use a communal toilet. These options are unhygienic, undignified and present particular risks for women. In rural areas people can build simple pit latrines and install a hygienic slab on top which keeps it safe. When the pit fills up they just cover it up and dig a new one elsewhere. But in urban areas with high population densities, this is not an option. In many unplanned settlements and even in some planned ones there is no sewerage. Across the world, forward thinking municipalities, NGOs and entrepreneurs are trialling systems to provide safe sanitation in low income urban areas.

This case study highlights the work which the non-profit partnership organisation, Water and Sanitation for the Urban Poor (WSUP), are doing in an area called Kanyama in Lusaka, Zambia. They are training pit latrine emptiers in hygienic practices, treating the waste they collect and transforming it into useful products. They are developing a sustainable business model which can be used elsewhere in Lusaka and across the world.

LEARNING OUTCOMES

  1. Understand the challenges in providing sanitation in low income urban areas
  2. Design an anaerobic digester for pit latrine waste
  3. Understand some possible alternatives to pit latrines

STUDENT ACTIVITIES

Class Activity: design a suitable anaerobic digester based on the population served, waste characteristics, and ambient temperature, and estimate the amount of biogas produced and the frequency and amount of waste digestate that would need to be withdrawn from the digester.

Homework Activity: students research alternatives to pit latrines and write a four page brief on one of the alternatives.