With Johannesburg suffering water shortages, Biénne Huisman looks at how another South African city learned from narrowly escaping "Day Zero".
by Biénne Huisman, bird story agency
Every day, residents of South Africa’s economic hub, Johannesburg, wake up wondering whether there will be water in their taps. Just more than 1,000 kilometres away, in Gqeberha, a water crisis is unfolding, too. These won't be the last African cities to worry over a looming "Day Zero" when water runs out. But there are ways to avoid it happening.
Cape Town has been there and done that – and knows that without careful planning and preparation, there could easily be a repeat of 2018’s “Day Zero” crisis.
“Day Zero” was to mark the onset of Level 7 water restrictions in the city. This would have seen most of its municipal taps switched off and residents queuing for daily rations of water.
During the recent multi-year Cape Town drought – which lasted from 2015 until 2017 and which experts described as a one-in-590-year phenomenon – the city council dramatically curtailed water demand. Capetonians rallied together in an unprecedented surge of citizen accountability, reducing consumption by letting gardens dry out, reusing grey water, reporting leaks, showering in buckets and being frugal when it came to flushing toilets.
Tears of elation flowed when generous winter rainfall in June 2018 averted the drastic “Day Zero” measures. However, the incident shook the coastal city, highlighting major vulnerabilities in its water supply.
Cape Town has an estimated population of 4.6 million - with up to two million additional residents expected to move in, over the next 20 years. Until the drought, its main water supply was from six rain-fed dams, including Theewaterskloof Dam, the city’s largest reservoir with a capacity of 480 million cubic metres (that’s the equivalent of 192,000 Olympic-sized swimming pools). In January 2018, the dam’s capacity shrank to 13%. Photographs of its parched bottom, with long-submerged trees standing like scarecrows in the dust, were published around the world.
Today, water use in Cape Town remains reduced at around 148 litres per person per day, compared to 200 litres per person per day before the drought. Messaging such as “save water” and “use water sparingly” are still a common sight in public bathrooms. However, concerned citizens have pointed out that enforcing reduced consumption is not a feasible long-term strategy for water security. The local government agrees.
No day zero [Image source: Africa Insights]
Cape Town city bosses concur that water scheme diversification – obtaining water from alternative sources to complement that generated by rain run-off – is key to avoiding future drought disasters.
And they say that these plans and infrastructure need to be rolled out fast. Inside Cape Town’s Civic Centre – the seat of the city council – executive director of water and sanitation, Michael Webster, agrees that harsh lessons were learned.
“I think from earlier [before the crisis], there should have been a bigger wake up call,” Webster says.
“Either way, we needed a massive shock to now get into a much less comfortable situation. This was a one-in-590-year drought. It really was unprecedented. That being said, climate scientists predict that Cape Town will become drier and experience more severe droughts more frequently.”
He refers to the United Nations’ sixth Intergovernmental Panel for Climate Change (IPCC) report issued earlier this year. In the chapter on Africa, the report states: “Increasing mean and extreme temperature trends across Africa are attributable to human-caused climate change... Multi-year droughts have become more frequent in west Africa, and the 2015–2017 Cape Town drought was three times more likely due to human-caused climate change.”
And of course, Cape Town isn’t the only African city staring down the climate change-driven drought barrel. The IPCC report names Dodoma, Tanzania’s capital, as another vulnerable city, warning that both it and Cape Town are “cases that illustrate challenges for both surface and groundwater supply”. Large swathes of Kenya, Somalia and Ethiopia are in the grips of another almost unprecedented event: the University of Brighton’s Professor David Nash says that four consecutive rainy seasons have failed since 2020, a phenomenon which hasn’t occurred in at least 40 years.
Preparation will be key to staving off these harsh new realities. In Cape Town, Webster says that while the council knew for over a decade that water demand was starting to outstrip supply, it was only the recent drought that prompted action to “rapidly accelerate” the rollout of new, diverse, water schemes. These include putting more resources into clearing programmes for “thirsty” alien vegetation – notably a R50 million (US$ 2,741,000) two-year partnership with global environmental nonprofit, The Nature Conservancy.
“There are alien invasive species like pines and blue gum that we’re cutting down,” says Webster. “So as to get out more water from catchment areas. This is actually our cheapest source of water and is a priority.” The city estimates that fast-growing alien plants reduce the amount of water reaching rivers and dams by around 55 million cubic metres a year, leading to a loss of 73 million litres of a day.
Another alternate water strategy is refurbishing and recharging the city’s three big aquifers – the Cape Flats Aquifer, the Table Mountain Group Aquifer, and the Atlantis Aquifer – allowing for water accumulation and storage underground. Aquifers are naturally occurring underground layers of rock that hold water. Managed Aquifer Recharge [MAR], also referred to as artificial recharge, is the process by which water is intentionally injected into an aquifer. Known as “groundwater sources”, the city predicts aquifers will account for 7% of future water supply.
A new desalination plant is being planned, similar to those built in drought-ridden Australian cities like Perth, along with a new wastewater reuse plant – the Faure New Water Scheme – which city authorities expect to be the largest direct reuse plant in the world when it starts operating in 2027.
“A sobering example for us is Perth in Australia,” says Webster. “Perth is the same latitude, a similar size, slightly smaller than Cape Town, also heavily reliant on rainfall and their dams. Over the last 50 years - from the seventies -their rainfall coming into their dams has reduced by over 80%. They successfully implemented desalination.”
The City of Cape Town’s director of bulk services for water and sanitation, Michael Killick, says: “We are busy doing a desalination feasibility study. Indications are that it will cost double the cost of a wastewater reuse scheme. [The budget for the Faure New Water Scheme is just over R2 billion].”
He adds: “The thing is, Australia has a much bigger income base than us. So, they can afford desalination. Desalination is also very energy-intensive, and we've got load-shedding [rolling power cuts], with the cost of electricity going up. One of the benefits of the Faure New Water Scheme is that the water treatment plant will generate its own electricity.”
The Faure New Water Scheme, says Killick, will combine the latest purification technologies for perfectly safe drinking water. Over ten years, the city’s water and sanitation budget is expected to be R40 billion (US$2,192,000).
“The aquifers, they’re earmarked to be fully running around 2027,” says Killick. “The reuse plant by the end of 2027, and desalination we want going by 2030. So, we’ve given ourselves 10 years, and within those 10 years we want to increase Cape Town’s water supply by about 300 megaliters [300 million litres] a day.”
Interim Director of the University of Cape Town’s Future Water research institute, Professor Kirsty Carden, concurs with Webster: the recent drought was an acute shock. She says she is familiar with the city’s new diversified water strategy and that she supports it.
“I think the major success with the new water strategy is that, for the first time, the city has shown real commitment to putting water at the forefront of its planning, for what is likely to be a very uncertain future,” says Carden.
“The major vulnerability plays out in the actual implementation of this transition; city officials, local residents, academia and other stakeholders will need to work together to achieve the vision of a water-sensitive city.”
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