Suitability of roof harvested rainwater for potential potable water production : a scoping review

The aim of the study was to devise a sustainable solution for drinking water supply in rural communities at an affordable cost, which is specifically related to the two of the United Nation’s Sustainable Development Goals: G3. Good health and well-being and G6. Clean water and sanitation. In this regard, the objective of this scoping review is to evaluate the sustainability, in relation to technical, financial and acceptability aspects, of a small-scale rainwater harvesting system to identify whether it can fulfil the demand of drinking water at a household level in rural communities at an affordable cost and in a sustainable manner. We have reviewed recent studies on rainwater harvesting systems to investigate: i. Whether a small scale system is economically and technically viable at rural community level, ii. Whether the quality of harvested rainwater meets drinking water standard, iii. Why rainwater harvesting system has not become mainstream water supply system as yet and iv. how climate change can affect the reliability of a small scale rainwater harvesting system? It is found that small scale roof connected rainwater harvesting system is likely to be economically and technically feasible when certain steps and risk assessment procedures are followed in designing and maintaining the system. It is also found that harvested rainwater needs robust treatment before human consumption. The public perceptions, capital cost, lack of knowledge on rainwater harvesting system, mix information about the quality of rainwater, risk associated with the system because of climate change, degradation of stored water quality with time and in some cases inadequate policies obstruct widespread adoption of rainwater harvesting technology. The world may see a dramatic change is socio-economic development of many rural areas when a sustainable drinking water supply system is established via a rainwater harvesting system.