Flowing with microbes

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

Three wetlands have been constructed to treat greywater run-off that leads into the Jukskei River. Residents who carry their tap water home use it for cooking, bathing and cleaning, but the disposal of this wastewater with inadequate 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 (BSc Eng 2000, PhD 2013), the URBWAT project lead. Using gravel-like beds with plants, a microbial biome has been established to 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,” says 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.”

Potable water test-strips app

Professor Sheridan is also director of the Centre in Water Research and Development (CIWaRD) and through the Claude Leon Foundation’s generous funding the centre launched its research on a potable water test-strips app recently. The idea is to dip a test strip into water, photograph an image of it and upload it onto the app, which will then generate an answer to the question of whether the water is potable, and if not, what must be done to make it potable. The team recently recruited its first master’s in electrical engineering student to start working on the app. With the completion of all process stages, the app should be available to the market by the end of 2024.

Source: Wits research news