Imagine if one day you turned on your faucet and nothing coming came out.
That prospect was almost a reality for the 4 million people in Cape Town, South Africa. Following years of crippling drought, the major coastal metropolis recently came dangerously close to Day Zero, the date it would have run almost entirely out of drinking water and had to shut off the taps, forcing residents to wait in lines for water rations. The ominous deadline was originally set for April 2018, but has since been pushed back to 2019 because of tightly enforced water-use restrictions. Since February, residents have only been allowed to use 50 liters of water -- 13.2 gallons -- per person per day (by contrast, the average American consumes an estimated 80 to 100 gallons a day).
Cape Town is the first major city in modern history to come that close to running out of water. But it’s likely not the last.
Major water shortages are predicted to become increasingly common in many cities and rural areas throughout the world, as urban populations surge, water consumption rises and climate change leads to more frequent and severe droughts.
Some 3 in 10 people -- about 2.1 billion people worldwide -- lack access to safe, readily available water at home, according to the World Health Organization. And at the current pace of growth and consumption, demand for freshwater is likely to soon far outpace global supply, according to one recent report.
Water covers about 70 percent of the Earth’s surface, but as the Above the Noise video “Is Earth Running Out of Water?” explains, less than 3 percent of that is freshwater. And most of that freshwater is locked up in ice or underground. Just over 1 percent is surface water -- from lakes and rivers. And the vast majority of that supply isn’t actually even used for human consumption; most of it goes towards agricultural production.
And as climate change leads to increasingly extreme weather patterns, it’s now more common for some places to have way too much water and others not nearly enough.
The issue is particularly pressing in the world’s rapidly growing urban areas, where roughly four billion people currently live. Some cities could soon face water crises as dire as the one in Cape Town. But a growing number of other dry, densely-populated areas have come up with innovative approaches to deal with water scarcity, efficiently managing and conserving their water supplies and recycling wastewater. The map below shows examples of cities threatened with potential water shortages and other places that have managed to successfully quench their thirst with smaller supply. [Note: this is just a sampling of water innovators and cities facing shortages - it’s far from a complete list.]
In addition to Earth’s dwindling supply of surface water, groundwater stored in aquifers is also an essential water source worldwide for human consumption and agriculture. More than 2 billion people rely on groundwater as their primary water source, including many people in the United States. But that supply is also being pumped out of the ground alarmingly fast and depleting reserves. According to one analysis of data from NASA’s GRACE satellite mission, water reserves in 21 of the 37 largest aquifers in the world have steadily declined just in the last decade. For more on aquifers, explore this interactive slideshow.