Extending the water life cycle in rural South African households: the role and potential of water reuse solutions

Abstract

Despite the issue of greywater management gaining more importance around the world, espe-cially in developing countries, it still remains a challenge in non-sewered areas of South Afri-ca. For a semi-arid country, reusing greywater on a household level has great potential as an alternative water source if done properly.
On a household level, the popular repurposing of greywater is for irrigation paired with simple technology. Although irrigation is a practical application, this study aims to extend the life cycle of water within the household by theoretically applying high-level technology to filter greywater within rural households of South Africa. Thus, greywater produced in the house-hold can be repurposed for close human contact activities like bathing, laundry and dishwash-ing. This will extend the life cycle of water within the household, increasing the availability of potable water in a household.
To achieve the aim of the study, Marulaneng village in South Africa was selected as a case study. 17 household surveys were done to collect data on their greywater production and wa-ter supply sources. The results reveal that people in Marulaneng are affected by the water scar-city in the country and use multiple water resources as coping measures. Their water consump-tion is half of what should be available to them according to the free basic service of 6 kilo litres per household per month, granted to all households by the government of South Africa.
Two household technologies were found to apply theoretically and extend the life cycle of water within the household. The reuse of rinse water from dishwashing would increase the availability of potable water by 10% and reusing bath water would increase the availability of potable water by 28%.

Popular Abstract

There is no doubt that access to clean and safe water is a necessity for all and has in the mod-ern world become an indicator of sustaining the environment, peace and humanity. In South Africa, a semi-arid country with a reputation of water scarcity, it is a constitutional right to have free basic water supply of 6 kilo litres per household per month. The management of greywater, wastewater generated by sources that are separate from human waste, has unfortu-nately not been as well established in legislation as water supply.
The reuse and recycling of domestic greywater has been identified as having significant poten-tial in decreasing the demand on freshwater resources. Although domestic greywater reuse is not explicitly mentioned, the targets of Sustainable Development Goal number 6 accentuate the importance of water reuse in ensuring water and sanitation for all. However, in South Af-rican non-sewered areas, greywater management remains an ongoing and pressing challenge. Without alternative options, households commonly dispose of greywater on the ground. A shame, considering the beneficial potential that greywater reuse has in socio-economic growth and alleviating high potable water costs in water scarce regions
Marulaneng village in South Africa suffers from inadequate water supply infrastructure and water scarcity. By determining the average amount of greywater produced in the households, the present study was able to estimate what the increase in availability of potable water would be if household greywater technologies were adapted in rural areas. The average amount of greywater produced per household per day was 71 litres. Interestingly, in the case where greywater production is assumed to be 75% of the total water consumption in households, Marulaneng households only use only 3 kilo litres of water per month. This falls 50% short of their basic human right. This should be an alarming result to government and decision makers considering that the residents of Marulaneng already use multiple water supply sources to cope with water scarcity. Greywater could serve as an alternative resource for some household activities.
Through literature research, one can see that the challenge is not whether or not greywater reuse is beneficial but rather what the appropriate use is without environment or health risks. The present study thus believes that because existing guidelines prohibits greywater reuse in non-sewered areas unless risks have been adequately addressed, it is important to develop household level greywater treatment technologies. Simple technologies are advocated for low-income, rural areas which are mostly developed for beneficial irrigation use. However, this study has found that potable water availability can be increased by 10% when reusing grey-water from rinse during dishwashing to wash dishes and 28% when reusing greywater from bathing for bathing and laundry. This requires a higher level of technology than the low-level technology provided presently.
These higher levels of technology can be found in urban households decreasing their water and energy consumption significantly. It is no secret that urban households use significantly more water than their rural counterparts, how much more then is such technology necessary in rural areas?

• author: Lehutjo, Tshepiso Kwena
• supervisor: Åsa Davidsson
• organization: Chemical Engineering (M.Sc.Eng.)
• course: VVAM01 20191
• year: 2019
• type: H2 - Master's Degree (Two Years)
• subject: Technology and Engineering
• keywords: greywater rural household technology, vattenförsörjningsteknik, avloppsteknik, water engineering, environmental engineering
• language: English
• id: 8984830
• date added to LUP: 2019-07-04 13:11:31
• date last changed: 2019-07-04 13:11:31