In March 2023, the South African department of water and sanitation celebrated national water month with advocacy and awareness campaigns to conserve and use water in a sustainable way.
In an interview with South African broadcaster NewzRoom Afrika, water minister Senzo Mchunu claimed that the water restrictions being experienced by many residents of Gauteng province were a result of high water consumption.
Gauteng residents used up to 233 litres per person per day, he said, "far above the average of 173 [litres] worldwide". Shortly afterwards, he quoted an even higher figure, saying "in Gauteng alone, they consume about 300" litres per person per day.
Africa Checked investigated this claim in January 2023 when Rand Water, Gauteng's water utility, claimed that the province's water consumption per person per day was over 300 litres, against a world average of 173 litres.
We were alerted to Mchunu's statement through artificial intelligence (AI) tools that monitor repeat instances of the same claim. Here's why it's still incorrect.
Consumption in Gauteng lower than 300 litres per person a day
South Africa has nine water management areas (WMAs). These determine how water resources are used in specific regions.
Rand Water supplies water to municipalities in the Vaal WMA, which covers the provinces of Gauteng, the Free State, North West and Mpumalanga.
In January, Rand Water spokesperson Makenosi Maroo told Africa Check that the average daily supply of water to municipalities in these provinces had increased from 4.3 billion litres to 4.9 billion litres since September 2022.
About 17 million people live in the municipalities served by Rand Water, she said. These figures do translate into an average consumption of almost 300 litres per person a day. But this is for the entire Vaal WMA, not just Gauteng.
Moreover, water use cannot simply be calculated by dividing the water supply by the number of people in a municipality, Kobus Du Plessis, a professor of hydrology and environmental engineering at Stellenbosch University in the Western Cape province, previously told Africa Check. Such a calculation ignores water used by industry, and the water lost through leaky old infrastructure.
Total individual consumption would therefore be less than 300 litres per person per day.
No accurate figure for average global consumption
The water department has previously admitted that the world average use of 173 litres per person per day "does not appear in any report but is based on expert opinion".
The figure comes from a 2012 report for the Water Research Commission, an organisation that coordinates water research in South Africa. It used data from the International Benchmarking Network (IBNET) on water use in about 150 countries to estimate the global average daily consumption in litres.
However, IBNET has cautioned against using its country averages to estimate a global average, because local government data from several countries was unavailable.
Prof Heinz Jacobs, former head of the civil engineering department at Stellenbosch University, previously told Africa Check that he "cannot imagine anybody at any institution anywhere in the world has an accurate figure for global per capita water use estimation".
Some publications might estimate the number, he said, but it would not be of much use because "many millions of people in the world use water from all sorts of ad hoc sources, without it ever being metered".
Varying climates, population sizes and housing systems, even within a single country, also make it difficult to accurately determine a global average of water per person.
South Africa is water scarce but high consumption not necessarily the problem
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According to various experts, water consumption by consumers in Gauteng is not particularly high. The bigger challenge is the large volume of water that leaks from the distribution system of the dilapidated water infrastructure and does not reach consumers.
According to the national water services knowledge system, maintained by the department of water and sanitation, South Africa's non-revenue water ratio was 47.5% in 2021. This is water for which municipalities didn't earn revenue, including water lost through physical leakage, commercial losses, and authorised consumption of water that is not billed. The figure for Gauteng was 42.1%.
In his interview Mchunu conceded that a gradual upgrade of water infrastructure was needed. But he did so only after identifying water consumption as the main problem and using debunked figures. The risk is that these flawed statistics are used to inform policy and allocate resources.
