The public was recently shocked to hear of the loss of life due to cholera in the Hammanskraal area. Panic swiftly fanned the flames of discontent as efforts were made to find evidence that cholera is lurking in other parts of the country. We now have a confirmed death rate of 32, with two coming from the Free State, proving that the cholera crisis is wider than Hammanskraal. 

The loss of life is tragic, but have we learned anything from history that might inform the present?

The epicentre of the 2023 cholera crisis is undoubtedly Hammanskraal, with a smoking gun being the Rooiwal Wastewater Treatment Works (WWTW) where a clear trail of forensic evidence of corruption, malfeasance and tender rigging exists. But, at the time of writing, no clear linkage has been claimed by any investigating authority. The news cycle has passed, so maybe the hope is that public interest will fade, before demands are made for a clear pronouncement on discovery of the epicentre?

Let me expand on this by using a tool accepted in the procedure and science of investigation. That tool is known as Occam’s Razor, and it basically says that when solving a complex problem with competing hypothetical solutions, the most probable solution is the one with the least number of assumptions. Stated differently, it tells us that the simplest explanation is statistically likely to be the correct one. 

How does this apply to the 2023 cholera crisis?

Let us start with fundamental facts that cannot be disputed. In 1831 a new and yet unknown epidemic hit London. It triggered panic that spread like wildfire. This led to the discovery of cholera as a new disease, alongside typhoid and scarlet fever. Doctors were unfamiliar with the new disease, adding to the sense of panic. In 1837 an outbreak of influenza, followed a year later by an outbreak of typhoid, wreaked havoc in the crowded slums of London. This resulted in the publication of a paper entitled The Sanitary Conditions of the Labouring Population by Edwin Chadwick in 1842. This caused Chadwick to be appointed to the board of the Sanitary Commission of London. The rudimentary sewage systems caused pollution of the River Thames, which was also the source of drinking water for the city of London. The dominant theory at that time was that disease was caused by “miasma” or bad air. This became known as “mala airia”, the root of the word malaria. 

A new theory started to emerge, challenging the dominant belief in miasma, which gained traction in the Middle Ages after it was observed that illness was associated with smelly conditions. The new theory was based on the observation that disease was transmitted from person to person and became known as contagion theory. Sanitation engineering was based on these two theories. It was believed that by removing the source of foul air associated with miasma, and restricting the movement of people with infection rooted in the experiences of the Black Death, the impact of disease could be limited. 

In 1849 there was a second outbreak of cholera, followed by a larger event in 1854, showing weaknesses in the prevailing sanitation engineering approach. John Snow, a physician, published a paper in 1849 entitled On the Mode of Communication of Cholera, in which he proposed that it was not transmitted by miasma (bad air), but rather by water. Armed with this idea, he used the 1854 cholera epidemic to conduct a statistical survey of all known casualties. He was thus able to isolate the source of the outbreak to one water point – a well with a hand pump – in Broad Street. Further investigation revealed a sewer carrying untreated human waste that was leaking into the well. 

However, as with all new scientific discoveries, there was scepticism from William Farr, in his capacity as head of the General Register Office. Farr challenged Snow’s statistical finding, thereby preventing proposed restoration work for the entire sewage system. It therefore took a fourth outbreak of cholera in 1866 to convince Farr of the veracity of Snow’s discovery. William Farr then published a monograph showing that the mortality was extremely high for people drawing water from the Old Ford Reservoir in East London. With Farr’s endorsement of Snow’s initial discovery, the theory that cholera was contracted by direct contact with sewage was accepted. 

With this fact now established, it took another catastrophe to bring about change. In the summer of 1858, the smell of sewage in the Thames River became so bad, that Parliament was forced to close. This event came to be known as the Great Stink and it catalysed the desire by the political leadership to intervene with policy that enabled the launching of what became the greatest engineering project of the era – a modern sewer system for London. That task fell to Joseph Bazalgette, Chief Engineer of London’s Metropolitan Board of Works. The new sewage system was commissioned in 1865, three decades after the first cholera outbreak that caused massive loss of human life.    

We therefore know, without the need to reinvent the wheel, that cholera is caused by sewage in the rivers. 

Green Drop Report

Let us now apply Occam’s Razor to this known fact by taking the next leap in logic. In 2013, the last Green Drop report allowed by Nomvula Mokonyane, in her capacity as Minister of Water and Sanitation, indicated that 248 of 824 WWTWs (30%) were in a critical condition. She chose unilaterally to suppress reporting of this reality as it might impact negatively on the public perception of the ruling party in an election cycle. In April 2022 the reinstated Green Drop Report indicated that 334 out of 850 WWTWs were in critical condition. That was a total of 39% of all WWTWs in 90 municipalities. The situation has significantly deteriorated. 

We know that we collectively discharge over 5-billion litres of sewage daily into our rivers. We also know that about 15% of that is treated to a satisfactory standard, the rest of which comes from the 334 dysfunctional WWTWs. However, we now also know that 41% of our drinking water systems (Blue Drop Watch Report) are non-compliant on microbiological parameters, with a further 9% being in poor condition. This means that 50% of the drinking water is non-compliant on microbiological standards. A red flag indeed.

So, to summarise, we have almost 40% of all WWTWs dysfunctional, and 50% of all potable water non-compliant in terms of parameters associated with risk of infection of one sort or another.    

Let us now apply Occam’s Razor to reach a plausible conclusion as to the source of the problem. We know that on 16 February 2001, Exception No 1918B was issued in response to a crisis at Rooiwal. This failed to correct the problem, so on 28 September 2011, a Plan of Action for Rooiwal Wastewater Works was presented for approval. On 3 October 2011 the Strategic Executive Director of Public Works and Infrastructure Development signed a document, copied to the City Manager and Executive Mayor of Tshwane. Based on this document, a State of Emergency was declared on 7 October 2011.  This provides clear indication of a crisis needing priority management, as well as naming names of who knew what and when they knew it. On 3 November 2011 DR6041/2011 was issued by the Department of Water and Sanitation. This is entitled Request for Deviation from Official Procurement Process. This enabled procurement of services to bypass the normal tender procedure. 

What we learn from the history of cholera

We can therefore say with confidence that the procurement procedures for engineering services arising from a situation so grave that a state of emergency had to be declared, lies at the heart of the 2023 cholera crisis. We also know that water was being provided by tanker services, so the most logical place to investigate the cause is the source of water from which those tankers were filled. Now we jump into the unknown, because the investigation has been focussed on the drinking water supply. But we know from observed cases in KwaZulu-Natal, that tankers are operated by syndicates who get paid per bowser delivered, and they often source their water in the river rather than waiting for hours in a queue at the municipal standpipe. We can therefore say, with the confidence provided by Occam, that the most probable cause of the infection was contaminated water delivered in tankers but sourced from the river. We know of course that Rooiwal WWTW has been discharging thousands of tons of sludge into a wetland along the Apies, the very same river from which the tankers have probably been sourcing their water. 

What we learn from the history of cholera is that resistance to implement fundamental human health management practices, first learned in London in the 1800s, costs human lives. Instead of waving their hands and feigning incredulity by focussing only on the drinking water system, investigators ought to look at the tankers sourced via a corrupted procurement process. Remember Occam’s Razor tells us that the simplest solution to any complex problem is most probably the correct solution. 

Written by Professor Anthony Turton, Centre for Environmental Management, University of Free State