What Happens When a Major World City Runs Dry?

CAPE TOWN, South Africa — Residents of this coastal city of 4 million have begun stockpiling bottled water and lining up at natural springs. The reason? Cape Town, a global tourist destination and South Africa’s second-largest city, may soon switch off its taps.

Dams are running low in the midst of an extreme three-year drought, one that has been compounded by extended delays in new infrastructure investments. “Day Zero” — the date when officials plan to shut down the municipal supply and start dispensing rations from some 200 collection points — is now expected to arrive in June, a month after the winter rains usually begin.

This would make Cape Town the second major global city, after São Paulo, to run dry in the last three years: a cautionary example for other governments in an era of climate change and a potential trigger for severe local unrest and disease outbreaks.

“The challenge exceeds anything a major city has had to face anywhere in the world since the Second World War or 9/11,” wrote Helen Zille, the premier of Western Cape province, where Cape Town is located, in a January column announcing that Day Zero had “moved from the realm of possibility to probability.” Water management spans national, provincial, and local spheres of government, and Zille’s party shares some responsibility — though how much is hotly debated — for the current crisis.

Daily water restrictions were slashed to 13 gallons per person on Feb. 1, with steep penalties for defaulters, as the city ramped up desperate efforts to stretch its reserves as far as possible. It is illegal to water gardens or wash cars with municipal water, and the city has encouraged residents to shower for less than a minute and limit toilet flushing.

“It is the only way that we can avoid Day Zero,” says Ian Neilson, the deputy mayor of Cape Town, who is now in charge of coordinating the city’s drought response.

As of Jan. 29, only slightly more than half the city’s residents had met the previous savings target of 23 gallons per person per day, officials said. In a city characterized by extreme income inequality, with a quarter of the city’s residents living in poorly serviced townships, water use patterns are heavily skewed: Last year, impoverished informal settlements on the city’s outskirts accounted for less than 4 percent of Cape Town’s water consumption, while the opulent suburbs, with gardens and swimming pools, used almost 65 percent.

According to Piotr Wolski, a climate scientist at the University of Cape Town, severe droughts like the current one take place roughly once every 300 years. But rainfall records show that the region’s climate has become hotter and drier over the last century, a pattern that climate models project extending in decades to come.

Several other major cities now face similar threats as urban populations grow and rainfall becomes less predictable. An El Niño drought in 2015 led to severe disruptions in Sao Paulo, Brazil’s most populous city, with taps in some areas cut off for days at a time. Melbourne, in Australia, has preemptively set savings targets to avoid overshooting the capacity of a desalination plant constructed during the so-called millennium drought of the 2000s.

Compounding Cape Town’s extreme spell of low rainfall has been a divisive political battle over water management, with the city and province, both run by the opposition Democratic Alliance party, locking horns with the national government, led by the African National Congress. The city sources its water from the national Department of Water Affairs, sharing annual allocations with other local municipalities and the commercially important agricultural sector, which usually uses about 30 percent of the total supply but last week began donating billions of gallons of water to the city to avert Day Zero. As the crisis has worsened, both parties have blamed each other for poor planning.

“The city doesn’t have the mandate to invest in new dams,” says Jodi Allemeier, a program leader at the Western Cape Economic Development Partnership, an institution that mediates between the private sector and different spheres of government. “But with a broader interpretation of their mandate the city could have been far more resilient.”

One thing the city could have done is use planning regulations to make rainwater tanks and on-site effluent treatment mandatory at the dozens of new developments approved in Cape Town. “Relying exclusively on big dams for water is an old paradigm. Cities at risk of drought should be moving towards decentralized water access,” Allemeier says.

With Day Zero fast approaching, the city has opted for a more immediate fix: urgently drilling boreholes to tap into a large aquifer beneath the city and building four desalination plants along the coast. These will supply enough fresh water to delay, though not entirely avert, the shutdown of municipal supply, but questions remain about the long-term economic and environmental costs of these interventions.

In the meantime, residents asked to live on a sixth of the water the average American uses are finding new ways to cut their consumption, adjusting to what officials have termed “the new normal.”

“I’m flushing the toilet once a day and showering once a week,” says Razia Blanchard, 66, after waiting in line for two hours to fill water at a public spring below Table Mountain. “What more can I do? This is terrifying.”

Plastic containers for storing water have been selling out as people brace for further restrictions. Day Zero rations — which may continue for several months until the reservoirs are replenished — will be just 6.5 gallons per person per day.

At Makro, a discount supermarket chain, customers were filling their carts with bottled water as quickly as workers could bring in new boxes. Most stores have begun limiting individual water purchases to reduce conflict in the aisles.

Fights at the springs have driven the city to repurpose an empty public swimming pool as a distribution point. The army is on standby to maintain order if Day Zero arrives.

Public health is another concern as residents switch to using gray water in toilets and gardens and the prospect of sanitation failure looms. WWF South Africa, an environmental group, has issued guidelines for treating and storing water. A January listeriosis outbreak that killed more than 18 people in the province has put officials on high alert. Wayne Smith, the head of disaster medicine at the provincial health department‚ says cholera‚ typhoid, and dysentery could easily spread following disruptions to the water supply.

According to city officials, Day Zero can still be averted if Cape Town reduces its total water consumption by an additional 25 percent. Already, daily usage has dropped from more than 260 million gallons to 142 million gallons within a year.

But for many residents in the townships that flank Cape Town, where more than 1.5 million people live at or below the poverty line, lining up for water at public taps is a routine activity.

“Unless you wake up early, you must wait in line for two hours,” says Aneliswa Biko, 23, who hails from a forlorn shantytown called Sqalo. Established within the last decade, the cluster of perhaps 5,000 shacks has no electricity and fewer than 30 taps.

“I carry 20 liters [5 gallons] every day. Our water is too scarce. What is this Day Zero people are talking about?”