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When Nomvula Mokonyane decided to suspend the Blue and Green Drop reporting system, she unleashed a fog of suspicion over the safety and security of our national water supply.
After Senzo Mchunu became Minister of Water, he promised to reinstate the same reporting system, and the information now emerging paints a bleak picture of a water sector in deep crisis. That slow-onset disaster has many dimensions to it, so today we are going to focus only on the wastewater aspect, to empower readers to make their own decisions.
When Minister Mchunu reinstated the Green Drop Report, we learned that we have 824 municipal wastewater treatment works, located in 850 municipalities, almost 40% of which are dysfunctional. This is relevant in the context of the alarming fact that a quarter of all municipalities are now ranked as being at ‘critical risk’ from a financial viability perspective. All are generally facing a leadership crisis, often with unstable coalition governments in the larger metros. All provinces are affected, but the most critical are the Northern and Eastern Cape, Free State, Limpopo, Northwest, and Mpumalanga. This is a provincial aggregate, which hides the fact that even in the provinces not mentioned, there are dysfunctional municipalities. There is a high correlation between municipal distress and wastewater treatment, to the point where we can safely say that as a rule of thumb, an indicator of municipal health is the quality of its wastewater treatment. No distressed municipalities have functional wastewater treatment plants, and many functional municipalities still have distressed wastewater treatment plants.
To understand what this means, we need to think of a river as a linear system that accumulates waste along its length. Given our unique geography, most of our population lives in the hinterland of the country, mostly on a high plateau consisting of grassland.
This population dispersal pattern is an artefact of history, mostly driven by mining on the Highveld and in the Free State Goldfields. This means that large cities have grown close to the points of origin of all our major rivers. The Witwatersrand, along which the greatest population density exists, is a massive urban conurbation ranging from Randfontein on the West Rand to Secunda on the East Rand. These are mining areas where huge mountains of waste have been disposed of, all of which leach toxic metals into the very headwaters of our big rivers – the Limpopo and Orange.
All rivers are consequently contaminated at the source, typically by mining waste, which includes uranium, arsenic, cadmium, and other metals. However, those same rivers are the source of drinking water for the entire population, while at the same time becoming the receiving bodies for wastewater discharged from sewage works. Hardly a news cycle goes by in which we don’t hear of raw sewage flowing into the nearest river. I am on record as saying that our sewage crisis is probably the root of an inevitable health catastrophe because it’s common knowledge that waste carries with it a range of substances that are harmful to humans.
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If we accept that all our drinking water is sourced from the nearest river, and once we understand that the municipality responsible for the safe treatment of sewage before disposal into the same river is in distress, we start to gain some perspective of the problem. Stated simply, a distressed municipality is unable to manage its wastewater properly, and we consequently have a growing flow of sewage contamination in our rivers. Let us give this some numbers to grasp the size of the problem. Our current population is around 60 million people, each of whom consumes about 200 litres of water per day. That equates to 12 billion litres of water daily that must be pumped from rivers, processed, reticulated and made available to each member of society. Of this, about half returns as waste to the sewage works. This gives us around 6 billion litres of waste per day, being treated by the 824 sewage works known to exist in the 850 municipalities. This consumes about a quarter of all electricity supplied to municipalities, with around 5% going just to the treatment of waste.
These numbers are staggering, but they exclude the thousands of package plants located in residential estates, dotted around the country, often along waterfronts or rivers. Delving deeper, we discover that wastewater contains a wide range of potentially harmful substances. We can divide these into chemical and biological. The chemically harmful elements include metals, some of which are a natural byproduct of corrosion in the municipal and domestic plumbing systems that use lead, copper and zinc. A distinct subset of these chemical hazards is related to the medications we use daily. All medicine is passed through the body and excreted as waste, often in a partially metabolised format. Sewage return flow therefore contains elevated levels of the types of drugs we use in society, including estrogen, antiretrovirals, antibiotics and mood-changing substances like antidepressants and recreational narcotics. A second subset of hazards relates to biological organisms, many of which are pathogens such as cholera, typhoid, legionella, hepatitis-A, and a range of viruses.
In wastewater works these two streams of waste come together. Biological organisms thrive in organic waste, but they are allowed to multiply in the presence of low doses of the very chemicals we use in medicines to destroy them as harmful pathogens. This runs the growing risk of breeding multi-drug-resistant organisms.
If we accept that our 824 municipal wastewater works, and many thousands of smaller package plants found in residential estates, collectively discharge into the same rivers and dams from which our 1,085 bulk water treatment plants produce potable water, we start to understand the nature of the problem we are confronted with. None of those potable water plants was ever designed to produce safe drinking water from sewage-contaminated raw water. This is the core challenge we face as a society today.
Our wastewater systems are all in crisis. Some of those are under the control of residential estates, so let us dwell for a moment on this specific aspect. Wastewater discharge standards for package plants are more lenient than those for municipal plants, based on the assumption that their volumes are lower, so the dilution factor plays in their favour. This is no longer the case, however, because we lost our dilution capacity when municipal wastewater plants became dysfunctional. Of the 6 billion litres of waste produced daily across the country, about 5 billion litres are outside the safety parameters for discharge into the environment. This means that our lakes and dams are now sources of nutrients upon which blue- green algae thrive. This needs a special article dedicated just to the implications of cyanobacteria, so all we can say in the space available is that we collectively need to become increasingly aware of the implications of our distressed wastewater management systems.
In closing, it is safe to predict that municipalities are unlikely to self-correct any time in the foreseeable future. This means that every citizen will need to understand the implications of our failing sewage infrastructure, and, where possible, start to internalise the solution. By this I mean that people living in residential estates are collectively capable of mandating their managing agents and bodies corporate for taking on the role of failing municipal service providers. This means that a savvy residential association will increasingly demand answers from their elected leadership.
