Cape Town marks a decade since its Day Zero drought began

This year marks 10 years since Cape Town endured a severe drought, a three-year period (2015-2017) that took the city of around 4.6 million residents to the brink of Day Zero – a point when Cape Town narrowly escaped running out of municipal water.

The drought, a once-in-590-year event, dramatically transformed daily life in Cape Town. Residents became acutely aware of every drop, adopting military-style showers, where taps were turned off while soaping, and water collected in buckets for later use, often for flushing toilets.

Queues formed at natural springs as people sought water beyond the strict municipal limits. “If it’s yellow, let it mellow” became a household mantra with signs still up at various bathrooms around Cape Town, and unwashed cars were seen not as a sign of neglect, but of civic pride.

The threat of Day Zero, when municipal taps would run dry, loomed large, creating a collective urgency and an ingrained shift in water behaviour.

This behavioural change, water restrictions, tariffs and a targeted information campaign led to a reduction in water consumption by half, which ultimately avoided the City of Cape Town officially turning off the taps.

Now, as Cape Town passes the 10th anniversary of the onset of the drought, the city has reflected on how the water situation has changed since 2015 and how progress has been made on safeguarding residents from future climate change-accelerated droughts.

The way the city is doing this is through its New Water Programme (NWP), which is set to add 300 million litres of water a day from new sources. The schemes to realise this include seawater desalination, groundwater extraction from aquifers and water reuse.

Hoping to increase public awareness of these schemes, the city held a media engagement with journalists on 29 July 2025 at its Zandvliet wastewater treatment works in Macassar.

This is the first of multiple engagements the city is planning with residents and civic groups across Cape Town to drive public awareness of the projects taking place in its NWP.

A new approach to water supply

The city is now trying to move away from its reliance on rainfall-fed dams, which supplied 98% of its water in 2015. This single-source system proved vulnerable during the drought, a period that climate studies have since shown was made three times more likely due to climate change.

Zahid Badroodien, the City of Cape Town’s mayoral committee member for water and sanitation, said: “Now we look beyond the drought. We look beyond the painful lessons that we’ve learnt.”

The NWP is the city’s long-term strategy to diversify its water sources and reduce reliance on dams. The goal is to add 300 million litres of new water daily from alternative sources by the end of 2031.

Mike Killick, director of bulk services at the city’s water and sanitation directorate, said that 98% of water in 2015 came from surface water, with only 2% coming from groundwater.

“That actually imposes an inherent risk should we have a drought… Our dams only offer us about two to three years of security from being full to almost a Day Zero situation,” said Killick.

While the current situation is positive, the city acknowledged that another drought was likely and could be an eventuality. But it is believed that the experiences of the past have taught valuable lessons, making the city better positioned to respond.

The initial target for major schemes in the NWP was 2030, but the estimated completion rate is now between 2031 to 2040. This adjustment, Badroodien said, was due to factors such as funding models and regulatory requirements, as much of this work had never previously really been done in the country.

Killick said, “We’re investigating how to implement these schemes. Will the city implement them, or will it be a public-private partnership (PPP)? Whatever we implement will have slightly different timelines. Council still needs to make a decision on that and they are hoping to do that by the end of this calendar year.”

Killick said the implementation of the NWP would not mean that Cape Town would never have water restrictions, but that “it’s going to reduce the severity of the impact on the consumer” should restrictions again be necessary.

“So we are going to have droughts, they are going to be more frequent, they’re going to be severe, but hopefully we can moderate that impact,” said Killick.

Some other key aspects of the NWP:

1. Removal of alien invasive species: These have been drinking billions of litres of water before it can enter dams.
2. Water reuse: This will be taking place at the Faure water treatment plant and reservoir in the coming years, where treated wastewater will be purified through an advanced new water purification plant to produce drinking water.
3. Desalination: The proposed permanent desalination plant (a seawater reverse osmosis plant) is planned at Paarden Eiland, costing an estimated R5-billion with a capacity of between 50 and 70 million litres a day (Mℓ/day).
4. Groundwater: The city is implementing a groundwater abstraction programme to supplement drinking water supply. On average, only 0.4% of water supply comes from groundwater. The city hopes to eventually increase drinking water from groundwater to 30%.

Read more: Groundwater — the hidden treasure beneath our feet is key to water security

The recently upgraded Zandvliet facility, where the media engagement was held, will be the key source of the “new water” in Cape Town. Treated wastewater from the Zandvliet treatment works will be sent to the Faure water treatment plant, located east of the city.

There, it will undergo an advanced purification process to produce potable water. This purified water will then be blended with existing dam water to boost the supply at the Faure plant, the city’s largest water treatment facility.

The augmented water supply will then be distributed into Cape Town’s broader water network.

Read more: Cape Town set to purify treated sewage water for drinking purposes

Cape Town’s water situation in 2015 vs 2025

Climate change is undeniably influencing Cape Town’s water future. The city’s water and sanitation executive director Leonardo Manus said, “We don’t have a conversation whether climate change exists or whether it’s not existing. We are evidently seeing in Cape Town what is happening here.”

City studies involving the University of the Western Cape (UWC) have shown that droughts will be more regular, more severe, and will last longer.

The rainfall patterns have also changed, with dams now filling up due to three to four very heavy rainy events rather than prolonged periods of low-volume rain.

Piotr Wolski, from the UCT Climate System Analysis Group, was part of the original World Weather Attribution (WWA) study that found climate change made the 2015-2018 drought three times more likely.

He told Daily Maverick that he believed the city was now “a lot better prepared for that eventuality, having gone through the Day Zero.”

Wolski said the most critical factor in avoiding Day Zero was the reduction in water use and the preservation of water, which was achieved through the collective actions of the people of Cape Town.

Ten years on, Cape Town’s water security has significantly improved. This is due to several factors.

There is overall reduced demand – Killick said that residential water consumption had substantially decreased from about 240 litres per person per day in 2015 to around 156 litres per person per day in 2025.

So it appears that people are using less water, a habit ingrained by the drought.

Cape Town primarily gets its drinking water from the Western Cape Water Supply System, a network of surface water sources managed by the national Department of Water and Sanitation. This system relies on rainwater collected in 14 dams, the largest being Theewaterskloof, Voëlvlei, Berg River, Wemmershoek and Steenbras Upper and Lower.

Killick said these dams were also at a better level and had been for the majority of the past three years, overflowing around the end of the rainy season, according to the city.

Wolski said that while the “new normal” didn’t mean perpetual drought, climate change increased the frequency and severity of droughts. He said it was not “if” but “when” another drought similar to the 2015-2018 event would hit.

While the city is currently “safe” in the short term due to full dams, the underlying vulnerability of a water supply system reliant solely on rainfall and dams, especially in a water-scarce region like this, remains.

Killick said, “Our dams only offer us about two to three years of security from being full to almost a Day Zero situation.”

The harsh realities of future droughts

Killick said at the time of the drought, there was possibly a public perception that the national Department of Water and Sanitation (DWS) and the city weren’t doing their planning, but “this was not correct.”

“DWS had done the Western Cape reconciliation strategy study, and we were busy with feasibility studies for a number of these schemes at the time. [But] what we didn't realise during the drought was the extent... 2017 was a one-in-330 year event, and the three-year period between 2015 and 2017 was a one-in-590 year event.

“So there is absolutely no way you can build infrastructure to carry you through a drought like that. The only option is to reduce demand,” said Killick.

But Killick said that climate change studies had been done, and a lot more homework, so they were better prepared for that eventuality after having gone through the Day Zero period.

City water and sanitation executive director Manus said the dams were now at a much better level, and people were generally using less water,  thereby decreasing demand.

From a climate change perspective, Badroodien said rainfall patterns had changed significantly. “Climate change certainly has an impact over time, which is why we’ve got to make sure that we’re building all of this now, for the future. Because what we also know is that another drought is likely… and all of this infrastructure has got to be ready for that eventuality.”

Building public trust and communication

A key challenge highlighted by Badroodien was the “growing trust deficit” between residents and local governments. Despite extensive efforts, he said there was a recognised need for better communication, as “the majority are not aware of the new water programme”.

Badroodien said that the city’s Water and Sanitation Department was not only in the business of water, but in the business of building trust with the public to ensure that residents “won’t be afraid of opening the tap and drinking their water”. DM