Appropriateness of low-cost sewerage for African cities: A questionnaire survey of expert opinion

Abstract

A questionnaire survey was circulated via internet-based sanitation forums to assess prevailing expert opinion about the appropriateness of low-cost sewerage for African cities. The questionnaire explored opinions about low-cost, solids-free sewerage (settled sewerage), low-cost, solids-transporting sewerage (simplified sewerage, condominial sewerage), and conventional solids-transporting sewerage. A total of 61 valid responses were obtained: 83 per cent of respondents considered low-cost sewerage to be ‘sometimes’ or ‘often’ appropriate for lower-income districts of African cities, versus 17 per cent who considered it ‘never’ or ‘very rarely’ appropriate. In contrast, only 44 per cent of respondents considered conventional sewerage to be ‘sometimes’ or ‘often’ appropriate. Thus low-cost sewerage is widely viewed as an important option to be given serious consideration during urban sanitation planning in African contexts. However, most respondents consider it appropriate only in certain specific situations, and many express concern about costs and long-term maintainability. Respondents’ comments concerning specific situations in which low-cost sewerage may be appropriate are discussed in detail