Lessons learned from the Cape Town water crisis

Lessons learned from the Cape Town water crisis

In 2017 and early 2018, Cape Town was in the grip of the most severe drought it had faced in over a century. Local and international media reported on the countdown to “Day Zero”, when South Africa’s legislative capital would become the first major city in the world to run out of municipal water.

Cape Town obtains nearly all its water from dams that capture rainfall during its rainy season in the winter months – from May to August. After dam levels began to decline in 2015, water restrictions were introduced in late 2016 and ratcheted up until early 2018 to try to reduce usage.

The curbs – including bans on using hosepipes, filling swimming pools and washing cars – were a direct policy response to the water shortage. Some were made permanent.

However, the crisis also spurred other initiatives, such as installing emergency desalination capacity. Schemes to re-use treated effluent were scaled up as officials rethought the management of certain water sources, for example ensuring the use of non-potable water for toilets. A less orthodox suggestion (ultimately not pursued) was to tow icebergs from Antarctica for use as fresh water.

Planning ahead is central to any policy, and two key lessons to take away from the Cape Town crisis are the need to create a robust water supply network and the need to better integrate climate change considerations into water planning. The response of residents is also vital in managing water demand and usage, and is the focus of this bulletin. In particular, is there anything that a country such as the UK could learn from how Capetonians behaved in response to the crisis?

The UK

One of the most enduring stereotypes about the UK is its wet weather. Every year, the media report on the disruption and damage caused by heavy rains and floods. The notion that the UK’s public water supplies will come under pressure by 2050 unless things change seems incongruous.

However, over the next 25 years, England is forecast to require an extra 3.4bn litres of water a day extra due to a combination of increased demand from a growing population and changes in rainfall patterns caused by climate change. Water UK estimates that between 2020 and 2050, droughts will mean that years when water restrictions are necessary will be twice as likely as in the 1997-2004 period.

Cape Town

Cape Town, with a population of around 4.2m, relies almost exclusively for its water supply on a rain-fed system of dams, known as the Western Cape Water Supply System (WCWSS). When restrictions were at their tightest, residents were limited to 50 litres per person per day, although water was not physically rationed. By contrast, the average Briton uses around 140 litres a day.

At their minimum during the crisis, Cape Town’s dams were on average 28% full. The largest WCWSS dam, Theewaterskloof, which accounts for just over half of total storage capacity, was a little more than 10% full in late April 2018. This was especially worrying given the difficulty of extracting water from dams when capacity falls below 10%.

Behavioural response

While the curbs helped to improve water efficiency and shift consumer behaviour, a peer-reviewed study carried out post-crisis found that the most dramatic behavioural change followed the publication of the city’s Critical Water Shortages Disaster Plan on 4 October 2017.

The plan addressed the risk of running out of water, the possibility of rationed drinking water being distributed at collection points and the increased threat of fire and disease in densely populated informal settlements. Its release touched off a media storm and user panic on social media.

Alerting Capetonians to the severity of the situation was potentially a risky strategy, but it may have helped prompt the most profound behavioural change: counterintuitively, the public’s response was not to hoard water but to reduce consumption. (By contrast, the imposition of further restrictions, such as a hosepipe ban, prior to the disaster plan’s release led to an increase in observed consumption.)

Other initiatives to change the way people used water included the following:

  • The launch of a publicly accessible city-wide map showing water consumption at a household level and highlighting significant users (discontinued post-crisis). While not targeted directly at individuals, this intervention is similar to social proof “nudges” aimed at cutting water use by showing residents which of their neighbours were at or below the monthly threshold for water consumption.
  • The launch of numerous communication campaigns in both traditional and social media providing water-saving tips.
  • The use of electronic signs on highways indicating how many days of water were left before ‘Day Zero’.
  • Businesses redoubled efforts to stress to their customers the need to save water. Hotels removed bath plugs and encouraged guests to take short 1-2 minute showers. Bars and restaurants displayed bathroom signs reading “if it’s yellow, let it mellow…” . And anecdotal evidence suggests that unwashed cars became a point of pride, while clean ones were looked upon unfavourably.

Implications for the UK

The UK and Cape Town are, of course, very different in terms of climate and infrastructure governance. In South Africa, water resources are managed by the national Department of Water and Sanitation. By contrast, the water industry in England and Wales is privatised; companies are responsible for providing and managing water, subject to economic, environmental and quality regulation via Ofwat, the Environment Agency and the Drinking Water Inspectorate.

An inference from Cape Town’s experience may be that users perceive and respond to communications from a local authority quite differently from those of a private company. To the extent that they do suffer from a trust deficit, private firms may therefore wish to work alongside experts such as environmental NGOs and independent regulators who enjoy the public’s confidence.

Capetonians were already aware that water is scarce where they live; their city is no stranger to water shortages. Britons, by contrast, think of the UK as a wet country. The challenge will be to change this perception so that the UK population comes to trust forecasts that water shortages will be a real threat and adjusts consumption accordingly. The way people behaved after the release of Cape Town’s disaster plan differed from the usual response to a crisis. Recall, for example, the hoarding of basic goods at the start of Covid lockdowns. Why this was the case raises the question whether the UK could rely on a similar response during a crisis.

However, we might draw some lessons – some more helpful in a period of calm, others more relevant during a crisis – from the behavioural response:

  • Water restrictions alone may not work – curbs on water usage might not lower demand as much as desired.
  • Highlighting the severity of a situation can be effective – as demonstrated by Cape Town’s disaster plan, coverage of a crisis in the media and discussion on social networks provokes a measurable reduction in consumption. However, it is a risky strategy: used regularly, the severity of the message could be diluted. Credibility is key. Is water really going to run out? Or, less sensationally, will some aquatic life suffer because river levels are low?
  • Stakeholder buy-in is important – facing such a crisis requires cooperation across the board, not just from households. Reminders from businesses to conserve water became ubiquitous. Working with all stakeholders is recognised to be essential in order to realise Water UK’s 2050 vision for the water sector. Because of the politics of a crisis in the UK, there will be an expectation that someone (the water companies) will need to be held to account in the event of a crisis. Attaching blame in this way risks becoming an excuse for consumers not to change their habits. That makes it fundamental to address the issue as a shared endeavour. Preparing the ground for that task is best done during a non-crisis period.
  • Behavioural interventions can be effective if implemented well – these can help in managing scarce water resources, in Cape Town’s case by naming and shaming large users.
  • There is no silver bullet – as in all crisis management, clear and coordinated messaging is fundamental. It is also difficult to disentangle the effect of any one intervention or initiative.

While lessons can be learned from Cape Town’s handling of the crisis, they are no substitute for long-term planning and strengthening the resilience of the water system by, for example, designing sustainable drainage, making more efficient use of water and protecting waterways and wetlands.


Happily, Cape Town’s water crisis came to an end with the return of rains in the 2018 rainy season. Interestingly, long-term usage has been creeping up slowly but remains below pre-crisis levels. This could be due to a number of factors: increased resilience; the installation of water-saving taps; people drawing more water from boreholes, which is not captured in the data; and lasting behavioural change as a result of greater public awareness.

With luck, the insights gained from Cape Town’s management of the crisis and the behavioural response of its residents might spare Britons the prospect of their taps running dry one day.