Plumbing Africa June 2018 | Page 35

HEALTH AND SANITATION 33 Guidelines for grey water use and management in South Africa: an introduction South Africa faces a range of challenges with respect to water management, including increasing demand for water and resource shortages. By Water Research Commission Environmental degradation, fragmented institutional structures, and basic services backlogs also form part of the range of challenges. Internationally, it is becoming increasingly accepted that a new approach to urban water management is needed. The World Water Analysis Partnership noted that "water management in urban areas can benefit from more comprehensive urban planning and integrated urban water management". Integrated Urban Water Management (IUWM) is an approach to urban water services that considers water supply, drainage, and sanitation as interdependent components of the integrated physical system known as the urban water cycle. As a result of this growing awareness of a need for change, the management and use of grey water (and other resource options aimed at diversifying water resources) as a viable alternative source of water for a range of 'fit for purpose' end-uses is being considered. Based on projected population growth, economic development rates, and the rate of urbanisation, it is unlikely that future demand for water in the country will be sustainable, and the availability of supply is likely to become a major restriction to future socio- economic development. an integrated water supply system. This project was thus aimed at providing the necessary guidance to support the wider adoption of domestic grey water management and use in South Africa to support the continued integration of the management of the urban water cycle. Treated grey water is already used in many countries throughout the world for household purposes, such as toilet flushing and irrigation of gardens; with recent research also considering the use of grey water to maintain 'green walls' (and thereby contributing to urban cooling) associated with large commercial/ residential developments. The management and use of grey water can pose significant risks, specifically in terms of the potential health and environmental hazards from chemical and microbiological contaminants and disease vectors, depending on the source of the grey water (for example serviced or unserviced settlements), the treatment process adopted (if any), and the use for which it is intended. Grey water quality is highly variable, and there is a need to develop guidelines to ensure the safe management and use of grey water as an alternate water resource, and also to limit and manage inappropriate disposal in areas where it has the potential to result in major health hazards; specifically, in low-income/'gap' housing and informal settlements. In South Africa, the use of (mostly) untreated grey water by individuals and companies has mainly been restricted to areas where alternative water sources are sought — often (but not always) during times of drought. This is partly owing to the fact that there remains little in the way of published local guidance as to how grey water systems should be designed, operated , and maintained as part of PROJECT AIMS Through the development of a set of guidelines, this project aimed to address (and mitigate) the risks associated with the management and use of domestic grey water, and support the wider uptake of this practice in South Africa — such that the diverse benefits that grey water use may offer can be realised. These include www.plumbingafrica.co.za A simple grey water system exclusively for garden irrigation. There remains little in the way of published local guidance as to how grey water systems should be designed, operated, and maintained as part of an integrated water supply system. Continued on page 35 >> June 2018 Volume 24 I Number 4