Clean water solutions made possible for Alex informal settlement through water-based research

11 November 2022 - Wits University

The Accessible Greywater Solutions for Urban Informal Townships (URBWAT) project is providing sustainable water solutions for the Alexandra township.

The saying Water Is Life proves true when it comes to its various uses, but it can also be extremely harmful when mixed with a range of disease-causing contaminants.

Globally, water resources are under threat. Increased urbanisation, increased industrialisation, increasing populations, climate change and pollution all have harmful effects on water as a resource.

The Accessible Greywater Solutions for Urban Informal Townships in South Africa (URBWAT) is a project studying the implementation of treatment wetlands in an urban megacity slum context.

Through URBWAT, three constructed wetlands have been built in a shanty portion of Alexandra township, Johannesburg to treat grey water run-off that ultimately leads to the Jukskei River.

Residents who carry their tap water home may wash fruit and vegetables, bath children, wash textiles, and clean the floor. Disposal of this wastewater amidst inadequate or non-existent drainage systems poses health and environmental risks. 

“There is probably a lot of black water too in greywater in South Africa, which has implications for people’s health,” says Professor Craig Sheridan, director of CIWaRD and the URBWAT project lead. 

 Constructing treatment solutions

A system of three constructed wetlands (CW) was built in gravel-like beds to establish a microbial consortium using plants that essentially eat chemical components in discarded wastewater. 

"Plants provide microhabitats for these microbes. It's an ecosystem service that we're mimicking from a natural environment under really stressed conditions," said Sheridan.

"What we're trying to do, is see if there is a way for us to treat it in-situ so that it doesn't just run through and it gets somewhat purified."

Increased urban populations with a lack of provision from civil services make the fight against clean, drinkable water challenging. Sheridan and his team of students and researchers have been working with the Alexandra community to ensure that the constructed wetlands positively impact the area.

In March 2020, the team worked with the community to design the current wetlands, with some of the building materials sourced locally.

In addition, a local artist was commissioned to paint a mural alongside one of the wetlands, to provide guided instructions on how to use the built structures. 

"The objective of this project is to try and solve some of these very difficult problems that we are going to have as a continent. This impacts everyone."

Essentially, the community using these systems have access to clean, purified water.

The impact of community-based research

Several postgraduate students from Wits University, Linköping University in Sweden and  the Helmholtz Zentrum für Umweltforschung - UFZ in Leipzig, Germany are part of this ongoing project. Those studying their Honours, Masters’ and Doctoral degrees are able to immerse themselves in the community and gain knowledge from notable research.

Microbiology master's student Michael Wilkie said that this kind of research gives him a better idea of how microbes work in these environments and the effects it has on the community.

"I've always been interested in microbes and what they can do for us. It's great to do something for the community and it's a good experience for me to understand how the bacteria works in a treatment system like this," said Michael.

He added that this research could assist in finding better solutions for water treatment systems across the country.

"I told my supervisor that I always wanted to be in an interdisciplinary project like this, and that's why I applied for it. The experience has been great because I get to meet new people. I've even met some people from my hometown, so I feel like part of the community," said Geography PhD student Motshwaedi Sepeng.

Students and researchers have since spent five weeks on-site this year, something that was almost impossible during the Covid-19 pandemic. The pandemic saw the collapse of some of the wetland infrastructure, sewage build-up and a disrupted ecosystem due to dying plants in the wetlands.

The latest data indicates that the wetlands are working and that there is significant remediation of the wastewater occurring within them. Research is ongoing to understand the extent of the remediation. A project extension has also been applied for to revise the design to prevent clogging of the wetlands.

The project will conclude in March 2033.

Integrated research across Engineering, Psychology and Biology

 A uniquely multidisciplinary project, URBWAT operates in the fields of engineering, the social sciences (psychology and geography), and the natural sciences (systems ecology and microbiology). While engineering and natural science objectives include evaluating the success of CWs in Alex to analyse and treat greywater there, social science objectives include assessing the attitudes and experiences of community members and other stakeholders to CWs, through workshops, focus groups, and surveys.

Water challenges for a changing world

Data from Statistics South Africa (StatsSA)'s General Household Survey indicate that 79.3% of households in South Africa live in formal dwellings, while 13.9% of households live in informal dwellings and 5.9% of households live in traditional dwellings. The sheer number of people (and the effect of wastewater treatment on health and thus on livelihood and prosperity) make the need for ‘adequate and equitable sanitation and hygiene’, and ‘improved water quality’, both by 2030, a priority.

The URBWAT project meets the dire need in South Africa for a low-cost, sustainable solution for informal settlements that lack adequate sanitary infrastructure. Ultimately, constructed wetlands have potential when temporary settlements have to be constructed to deal with an emergency – such as when people are displaced by fires or floods – or for use in refugee camps, where tent-dwellers have poor access to sewerage and/or greywater treatment.