The greywater situation in informal settlements of the Ekurhuleni Metropolitan Municipality - Eastern Region (Gauteng, South Africa) / by Nomvula M. Mofokeng

Abstract

In recent years growing attention of international and local water research was directed to greywater as a potential water source, as well as its significance as a possible health risk to humans and as a source of pollution. Owing to a general lack of waterborne sewage infrastructure, health risks and pollution associated with greywater generation in informal settlements are of particular concern to municipal managers. However, so far only limited information on the greywater generation, use and disposal in informal settlements is available. Using four different informal settlements in the highly urbanised eastern region of the Ekurhuleni Metropolitan Municipality in Gauteng (also known as East Rand) this study aims to characterise selected aspects of the greywater situation as a first step towards future improvements through appropriate interventions and greywater management. Following consultations with representatives of the local municipality (colleagues of the author) the following four informal settlements with distinctly different greywater appearance were selected as study sites: • Benoni - Harry Gwala • Springs - Gugulethu • Brakpan - Mkhanca • Nigel- Soul City As part of the reconnaissance phase of the study, each site was visited and field observations on infrastructure, habits and other greywater related aspects were made and suitable households for subsequent interviews were identified. In each settlement a total of 25 households were chosen and a representative interviewed using a pre-designed questionnaire comprising eight sections, four sections covering the following aspects: access to and sources of water, general sanitary situation, water use and associated generation as well as disposal of greywater. Interviews were conducted between November 2006 and August 2007 and varied in duration between 20 and 30 minutes per interviewee totalling close to 48 hours. They were either conducted in Zulu or South Sotho, the most widely spoken languages of the interviewed residents. Answers were recorded in English on site. Results were subsequently captured in EXCEL and statistically evaluated. The average volume of greywater generated by the four different water usages, Le. bathing, cleaning, laundry washing and dish washing varies from 35 to 60 /household/day. With each household comprising an average of four people (two children and two adults) this equals a greywater generation rate of approx. 9 to 15 l/person/day and is somewhat lower than reported in comparable studies in South Africa. Owing to the fact that all volume data are estimates, a comparatively large margin of error is to be expected, explaining why in some cases more water was estimated to be used than was actually fetched. Water use volume was found to be influenced by the availability of stand pipes and in one case was supplemented by collected rain water. Generally, however, water was not perceived to be a problematic issue compared to more pressing needs such as housing, unemployment etc. Washing of cloths in all settlements was found to be the single most important source of greywater generation accounting for a third to almost half of all greywater generated. The smallest contribution comes from water used for cleaning (approx. 10%) while bathing and washing dishes accounts for equal proportions of the reminder. Chemical and microbiological analyses of greywater, sampled at selected sites across the four study areas, revealed significant variations in quality between the different sites, without allowing for clear distinctions between the impacts of different brands of detergents such as soaps, washing powder and dish washing liquids. Contrary to literature E-coli contamination was found not be confined to bath and kitchen waste water only, but also appeared in laundry water, frequently exceeding values stipulated in the general standards of waste water or effluent in South Africa This is of particular concerns since some of the greywater is disposed of into stormwater canals and in other non-formal ways, that allow for subsequent exposure of humans to the contaminated waste water. In order to facilitate rapid drainage in some instances respondents created their own greywater disposal infrastructure e.g. by digging open waste water trenches across backyard borders. Regarding potential health risks it is to be noted that at least one respondent reported the use of the water resource (Blesbokspruit) as toilet facility. Apart from the actual findings the study also revealed the importance of an appropriate research design and conduct that addresses the peculiarities of an informal setting. This includes overcoming logistic challenges such as limited accessibility of the study sites during wet seasons owing to flooded and muddy roads, safety and security issues as well as difficulties to conduct indoor interviews owing to a lack of light (no windows, no electricity) leading to low temperatures in winter limiting interview duration. In addition to this socio-cultural aspects and attitudes of respondents have to be taken into account in order to obtain true reflections of facts through interviewing. In this regard it was helpful that the author, as a black female, was familiar with certain customs and perceptions regarding sensitive issues such as use of toilets, connotations of muti (= a traditional medicine that may be included in bathwater as a constituent) etc. Being aware of these peculiarities allowed the author to detect and explain differences between statements obtained from the respondents and her own observations.