Here's how we used Wazimap to support water quality monitoring.
Rivers of Sewage, a collaborative project between GroundUp, OpenUp and CCIJ, has recently been shortlisted for two prestigious awards — the international SIGMA awards for data-driven journalism, and the South African Taco Kuiper award for investigative journalism. Through a series of stories (see below), the team exposed the systemic national failure of municipal sewage treatment works, and its devastating effects.
- Child diarrhoea cases surge as sewage runs on Cape Town streets
- ‘A tsunami of human waste’
- Living in a ‘critical state’
- Communities turned into sewage swamps
- ‘The water is not good at all’
- Taking matters into their own hands
Our role in the project was to help investigators to explore the data captured by South Africa’s national Department of Water and Sanitation (DWS), in order to uncover where important stories lie. This data shows that more than half of all municipal sewage treatment works fail to treat sewage to the required minimum standards before releasing it into rivers.
In addition to the ecological damage, this pollution flows into dams supplying drinking water to citizens. Unsurprisingly, drinking water also fails to meet the prescribed minimum standards in two thirds of South African municipalities, with many municipalities failing to provide any water for days, sometimes weeks at a time.
Understanding the systems through which South Africa's wastewater travels, and is treated, requires navigating a lot of data. In this case, data for 1130 wastewater treatment works. To make navigating the data simple, we brought it into Wazimap.
Wazimap is a simple, but comprehensive GIS and data analysis tool developed by OpenUp, and helps tell these stories using geographic visualisations i.e., data on a map. For example, in ‘A tsunami of human waste’, Wazimap helps illustrate current (at the time of writing) states of wastewater treatment works (WWTWs) that the City of Cape Town is responsible for (first image above).
As the latest data (Feb 2023) shows, most WWTWs that the City of Cape Town is responsible for, have a Bad overall status. This means they are failing across one or more of their critical compliance criteria (i.e., their microbiological, chemical and physical compliances). For example, the Green Point WWTW (second image above), situated in Mouille Point, is failing in terms of its microbiological compliance — the concentration of faecal bacteria (such as E. coli) present in its outgoing sewage.
Green Point WWTW is also a marine outfall, which means the only treatment the outgoing sewage receives is maceration — pumping the sewage through a three milli-meter sieve to remove solids and grit. In spite of this, Green Point WWTW is not required to monitor or reduce the faecal bacteria in the sewage it releases into the ocean every day (40,000 kilolitres per day).
Similarly, Living in a ‘critical state’ uses Wazimap to highlight the critical state of WWTWs in the Free State province (third image above), where many WWTWs have never been monitored before (black dots). Of those that have been monitored, the Free State has only one Excellent (blue dot), one Good (green dot), and one Poor WWTW (yellow dot). The rest all share the status of Bad (red dots).
Wazimap provides journalists with a map-based data explorer to help support their understandings of local conditions (such as the water and sanitation conditions highlighted in the stories above). That this type of data-driven journalism is impactful, is evident.
It has, for example, contributed to Cape Town’s new mayor declaring sewage pollution a top priority, and the city now making the results of its inland and coastal water quality tests public. It is also believed that these stories (and others which led up to them) had some influence on the return of the Green Drop report (which had been halted in 2016).
The Rivers of Sewage project has also received a lot of interest from researchers, NGO’s, and other advocacy groups, outside of South Africa, wanting to reproduce the method.
The full WWTWs dataset can be explored on our Water Wazi ZA. Click here if you’re interested to know more about Wazimap.