Civil Engineering January/February 2021 | Vol 29 No 1

Civil Engineering January/February 2021 21 “Governments and policymakers have realised that improving WASH, including safe water, adequate sanitation and hygiene education, has a profound positive impact on public health. As far back as 2011, a World Health Organisation study, Water, sanitation and hygiene interven- tions and the prevention of diarrhoea , notes that water supply interventions can reduce incidence of diarrhoea, for example, by 5%, water quality interven- tions by 19% (after 12 months), sanitation interventions by 36% and handwashing interventions, alone, by a staggering 47% for hand washing with soap,” says Robyn Tompkins, Executive Associate of JG Afrika and the firm’s WASH Specialist. The focus of WASH projects includes preventing human contact with patho- gens, which is fundamental to the safe management of human excreta, including collection, treatment, disposal and associ- ated hygiene practices. According to the United Nations Joint Monitoring Programme report of 2019 titled Progress on household drinking water, sanitation and hygiene I 2000–2017 , only 40% of the global population has access to safely managed sanitation facilities and 3 billion people do not have adequate handwashing facilities at home. Even in 2019, almost 10% of the world’s population practised open defeca- tion. The situation is particularly bad in sub-Saharan Africa, where 72% of people do not have access to sanitation. ONSITE SANITATION There is a high reliance on on-site sanita- tion technologies, such as septic tanks or pit latrines. This is especially the case in peri-urban and rural areas of southern Africa where it may not always be feasible, or there is insufficient technical capacity or financing available, to implement and operate waterborne sewage systems. The safe management of faecal sludge across the sanitation service chain from the user interface (the toilet) to the point of end-use or disposal is therefore of critical importance in national planning. There is a real risk that humans will be exposed to human excreta at any point in the process. In some instances, treatment plants do not have sufficient capacity to adequately process the faecal sludge before releasing it into the environment. Furthermore, treatment plants are often designed for wastewater processing rather than faecal sludge processing, and man- agement systems are set up for sewage rather than faecal sludge. INNOVATIONS However, new sanitation technologies, which can be implemented faster and more cost-effectively than large, central- ised sanitation systems, are becoming increasingly available to developing econ- omies to help overcome these challenges. They have, therefore, become a significant focus point for WASH professionals. For example, innovative apps now allow community members to locate and book the services of the nearest private drainage operators which drives up the uptake of these services among low- income residents, as has been the case in Dakar, Senegal. Collection services were previously unaffordable for many of the city’s resi- dents and they would, therefore, rather manually remove the waste themselves or pay someone to do this on their behalf, Addressing sub-Saharan Africa’s inadequate sanitation The effectiveness of proper hygiene practices in managing the spread of Covid-19 has highlighted the critical importance of appropriate sanitation and good hygiene practise in managing disease transmission, leading to a greater interest in water, sanitation, and hygiene (WASH) projects. The sanitation value chain (Source: Bill and Melinda Gates Foundation ) Sanitation Value Chain Containment  Emptying Transport  Treatment   Refuse/Disposal