Rainwater harvesting systems to promote sustainable water management

Water is the vital source of life. Although the human race has made significant developments in many aspects of life, the very basic need of fresh drinking water has not been ensured to over one billion people globally. In recent years, water reuse, conservation and recycling are being promoted to meet the growing water demand, and in this regard, rainwater harvesting (RWH) has received significant attention. This paper presents an overview of research on RWH systems through a bibliometric analysis and summarizing research undertaken by the Water Engineering Group of Western Sydney University, Australia. The results of the bibliometric analysis show that the number of publications on RWH has been increasing significantly with time. It has been found that the USA, China, India, Australia and South Africa have published the highest number of articles on RWH. Rahman A (Australia, first author of this article) has the highest number of articles (34), followed by Ghisi E (Brazil) and Han M (South Korea) (26 articles) and by Butler D (UK) (25 articles). In RWH research, Rahman A (Australia) has received the highest citations (880), followed by Ward S (UK) (699) and Butler D (UK) (687). The Water Engineering Group in Western Sydney University (Australia) has developed a RWH Filtration Unit (RWH-FU) recently to produce drinking water at household level (at a capacity of 348±20 L per day). The economic payback time for the new RWH-FU is eight years, with a water production cost of about AU$ 0.07/L. This RWH-FU is expected to be widely adopted in rural areas globally. Furthermore, this research group has shown that RWH can significantly increase agricultural yields from household gardens (in Sydney, a 3 kL tank connected to a 200 m2 roof catchment can increase agricultural yields from 66 to 143 kg). RWH has been making a positive contribution to meet water related sustainable development goals, in particular Goal 2: Zero hunger; Goal 3: Good health and well-being, and Goal 6. Clean water and sanitation.