In 2018, Cape Town, South Africa, one of the wealthiest cities in Africa, faced the prospect of running out of water. This city of four million people was counting down the days to “Day Zero,” when they would turn on the taps and find them dry.
Ultimately, Cape Town's water conservation measures helped the city narrowly miss reaching Day Zero (for now).
However, the experience stands out as a warning of what's to come for large, developed population centers as climate change puts increasing pressure on the world's water in unprecedented and unexpected ways, from a mega-drought in the American West to drier soils preventing rivers and lakes from recharging when rain does arrive.
Cape Town is dealing with a scenario that a major developed city has never faced in the 21st century. “Day Zero” could be only three months away. https://t.co/9idHsCe3Nj— UN Environment (@UNEnvironment) February 8, 2018
There was little doubt that Capetown's three-year drought was made worse (and more likely) by climate change, which means the city will have to keep grappling with these challenges in the future.
“With climate change we need to do more with less,” said Mlungisi Johnson, chair of the South African Parliament's Portfolio on Water and Sanitation.
And South Africa is not alone in this challenge.
Why Aren't More Heavy Rains Filling up Water Supplies?
The historic droughts in South Africa, Australia, and the American Southwest were not unexpected consequences of climate change. However, a global study led by a team at the University of New South Wales in Australia recently revealed a troubling development that does not bode well for these kind of drought-stricken regions.
While — as expected — climate change has resulted in heavier rainfall (because warmer air can hold more moisture), this study found that these heavier rains are not leading to more available freshwater in large rivers, lakes, and reservoirs.
Instead, warmer temperatures are leading to drier soils that absorb more water from rainfall and allow less of it to travel through groundwater systems to recharge the rivers and reservoirs that provide drinking water to cities like Cape Town.
Professor Ashish Sharma, a civil and environmental engineering professor who led the study, was surprised by this finding.
“This is something that has been missed. We expected rainfall to increase,” Sharma said in a statement. “What we did not expect is that, despite all the extra rain everywhere in the world, the large rivers are drying out.”
Sharma noted the need to adapt and re-engineer water systems on a “massive scale” to take this shift into account. He points to Arizona and California as examples of large population centers that were able to do this in order to exist in areas that have nowhere near the rainfall or local water resources to support the existing populations.
Sharma said these areas have ”engineered their water supply systems to make previously uninhabitable places liveable.”
However, considering these areas' current water woes, they may not be the most promising examples to follow in a climate-changed future.
The Colorado River Crisis and America's Mega-Drought
Without water from the Colorado River, major U.S. cities like Las Vegas and Phoenix would not exist. However, they — and the Colorado River — are facing a water shortage crisis with no easy solution. And with 40 million Americans relying on the Colorado for water, this is no small problem.
The American West currently is experiencing what has been dubbed a “mega-drought,” a phenomenon that hasn’t occurred on the planet in the last 500 years. And as a team of researchers at Columbia University recently revealed, “global warming's fingerprints” are all over it.
Park Williams, a professor of bioclimatology at Columbia, said that climate change “caused what would have been a fairly severe drought to become a drought as severe as the most severe droughts of the last millennium.”
The team estimates that global warming made this mega-drought 62 percent more severe. They presented their results at a major earth science conference, but have not yet published them in a peer-reviewed scientific journal.
The Hoover Dam at Lake Mead. Credit: EcoFlight
Amid that mega-drought, the state of water supplies in the American West is frightening. Since 2000, the water flowing in the Colorado River is 19 percent below the average of the past century. Lake Mead, the lake created by the Hoover Dam and one of the main reservoirs in the Colorado River system, is at 38 percent capacity.
The federal government predicts Lake Mead will hit the critical “shortage” level by 2020, while others are predicting the lake could hit that level in 2019.
The latest @usbr Colorado River reservoir operations report came out during #CRWUA18, and it projects Lake Mead to drop below 1,075 feet (official shortage trigger) within six months, and stay below the level for the rest of 2019. https://t.co/I3YszSm9CE— Luke Runyon (@LukeRunyon) December 18, 2018
In December, the people and organizations responsible for dealing with this coming crisis met in Las Vegas. They were tasked with creating an agreement on how to allocate the Colorado's shrinking water resources, while knowing that cuts in supply are inevitable. The federal government has given this group until the end of January 2019 to come to an agreement.
As Kathryn Sorenson, director of Phoenix’s water utility, explains, that is no simple task:
“That’s a painful conversation. And of course everyone thinks that their own water use is justified and no one else’s is.”
Growth in population and agriculture at some point would have created greater demand for water from the Colorado River than could be supplied. However, climate change has brought that day of reckoning far sooner than most expected.
University of Michigan climate scientist Jonathan Overpeck coined the term “mega-drought” and recently explained why what is happening in the West and around the world has caught many by surprise.
“The warming is having a huge effect — a huge effect on water resources and a huge effect on forests,” Overpeck told The Atlantic. “People knew there would be an effect, but we didn’t know it would come this big, and this fast.”
To highlight that point, in 2015 NASA warned that a “mega-drought” could hit the American Southwest in the “coming decades,” which The Washington Post reported could “lead to monster wildfires in southern Arizona and parts of California.” But the latest research suggest that it may already be here.
The Water-Energy Nexus
These thirsty cities in the middle of deserts also require more and more air conditioning to deal with the extreme heat that climate change is also bringing.
Air conditioning has enabled Arizona to rank the fifth-highest population growth among U.S. states, but all those humming ACs require electricity. And the majority of electricity produced in America requires vast amounts of water. As climate change raises global temperatures and alters water distribution, water use in energy production — and specifically reducing it — will become increasingly important.
That brings up the stark contrast between America’s two fast-growing forms of electricity production — fracked natural gas and renewables (namely, wind and solar).
A Duke University study this year found that water use by the fracking industry had risen by 770 percent from 2011 to 2016. New Mexico, a state dealing with water shortages, meanwhile is setting records for fracking production. And it's basically the same story in Colorado and Texas.
Meanwhile, as the U.S. Energy Information Administration recently pointed out, producing electricity via wind and solar photovoltaic (PV) uses almost no water.
The California State Water Project was borne out of the state's acknowledgement that local water supplies and its share of the Colorado River would not be sufficient for its growth. Credit: Courtesy of the University of New South Wales.
Yet as Arizona faces a mega-drought and the likelihood of cutting water use in the near future, the fossil fuel industry successfully fought a ballot measure there requiring more renewable energy production.
And any agreement among users of the Colorado River is unlikely to adequately prepare the burgeoning region for what's coming down the line with climate change.
Arizona is growing and plans to grow more. Among other plans, a group backed by Bill Gates wants to build a whole new “smart” city from scratch in Arizona.
Keith Moses is vice chairman of the Colorado River Indian Tribal Council in Arizona, one of the many groups currently negotiating for its fair share of the river's water. Moses told The Associated Press that he knew that limiting growth was the best way to conserve water.
“Realistically, looking at it, that’s not going to happen,” he admitted.
However, the current water use plans for the Colorado River are considered stop-gap measures; they don’t even address the reality of climate change. Tom Buschatzke of the Arizona Department of Water Resources said these plans were “not really a climate-adaptation program” even though “we are anticipating a drier future.”
That drier (and warmer) future appears to be arriving much faster than expected for places like Cape Town and Phoenix. And yet business-as-usual seems to still be the order of the day.
After City Council rejected a water rate hike last week, the rating agency Moody's offers a few words: Not raising rates would be “credit negative” for the city's water utilityhttps://t.co/Nxxygfn7UB— Elizabeth Whitman (@elizabethwhitty) December 19, 2018
Main image: A drought-affected swimming hole. Credit: Courtsey of University of New South Wales