Almost half of the world’s population — some 3.6 billion people — currently live in areas vulnerable to water scarcity. By 2050, this is expected to increase to around 5 billion people, a new United Nations report warns.
Water quality issues and increased demand for water due to a growing global population will combine to put the world’s freshwater resources at risk, explains the World Water Development Report, released Monday. Growing threats from flooding and drought, worsened by climate change, will further exacerbate the issue.
The report warns of risks of increased conflicts and threats to human civilization unless action is taken to reduce stress on lands and wetlands. These ecosystems are vital to managing water resources but have been steadily deteriorating with increased human activity. This ecosystem degradation is the main cause behind increased “water-related risks and extremes,” the report explains.
Marshes, for instance, are an important buffer against storms. And soil plays a critical role in water storage and absorption — as soil quality deteriorates, more water evaporates, and more water simply runs off the land and contributes to erosion.
“There is evidence that such ecosystem change has over the course of history contributed to the demise of several ancient civilizations,” the report states. “A pertinent question nowadays is whether we can avoid the same fate.”
The demand for water is increasing by 1 percent each year due to population growth, economic development, and changing consumption patterns, according to the report. Global population numbers are expected to reach between 9.4 and 10.2 billion by 2050, up from 7.7 billion in 2017. Therefore, over the coming decades, the biggest expected growth in water demand will come from industry and domestic use. The majority of this demand will be in developing countries and emerging economies.
Within global industrial water use — which currently accounts for roughly 20 percent of all water withdrawals worldwide — energy production is responsible for three quarters of all industry’s water usage. The rest is used in manufacturing. Domestic water use accounts for 10 percent of the world’s water withdrawals.
Agriculture, however, will continue to make up the largest share of global water use going forward. Currently, it accounts for 70 percent of the world’s water withdrawals, which largely goes towards irrigation. Agriculture is also responsible for the biggest water quality challenge facing the world — runoff of polluting nutrients, such as nitrogen and phosphorus used in fertilizers, into groundwater sources.
Industrial and municipal wastewater also plays a big role in water pollution — about 80 percent of this wastewater enters the environment without any prior treatment.
Added on top of all of this are the impacts of climate change.
As global temperatures increase, wet regions will become wetter and drier regions will become even more dry. This will affect where and when water will be more abundant or limited. Changing patterns in rainfall will affect the worlds rivers, lakes, wetlands, and oceans. Meanwhile increased temperatures will make water evaporate more quickly from soils and plants. Extreme rain events will also likely result in more pollutants entering water resources.
The greatest exposure to these impacts will come in low- and lower-middle income countries because of greater expected population and economic growth in these areas.
About 30 percent of the world’s population is expected to live in areas at risk of routine flooding and drought. By 2050, between 4.8 and 5.7 billion people will live in regions that will be water-scarce for at least one month each year. Meanwhile, the number of people at risk from floods will increase from 1.2 to 1.6 billion.
Land degradation, desertification, and drought in particular is seen as “the most significant category of ‘natural disaster’ based on mortality and socio-economic impact relative to GDP per capita,” the U.N. report warns. Due to the long-term, “chronic” nature of droughts, the report states, they are “arguably the greatest single threat from climate change.”
Water scarcity isn’t an issue which will only be felt a couple decades from now, however. With a third of the world’s largest groundwater systems already in distress, “current global withdrawals are already near maximum sustainable levels,” the report warns.
The powerful threat of water scarcity has, for example, most recently been felt by those living in Cape Town, South Africa where residents are currently living under severe water restrictions due to a 1-in-384-year drought.
To help tackle water scarcity and quality issues, the report calls for greater use of what it calls “nature-based solutions” — solutions which look beyond just watershed management to a broader approach that takes into account land use in distant areas including forests. Recent studies highlighted by the report show that vegetation helps to recycle and redistribute water. Deforestation in the Amazon, for example, played a significant role in the 2014 São Paulo drought.
For agriculture, the report also recommends using practices that will help improve efficiency as well as soil quality. This can be done through tactics like more regular crop rotation and greater use of rainwater. As more of the world’s population lives in cities, urban water usage will also need to be a key focus for improvement. And, as the report highlights, “given the transboundary nature of most river basis, regional cooperation will be critical to addressing projected water quality challenges.”
Pointing to these growing trends of water pollution and environmental degradation combined with increased water demand, Audrey Azoulay, director-general of Unesco, which commissioned the report, said: “These trends pose broader challenges from the increased risk of floods and droughts, which in turn has an impact on our ability to adapt to climate change. We know also that water scarcity can lead to civil unrest, mass migration, and even to conflict within and between countries.”
“The stakes are high,” said Azoulay. “Today, more than ever, we must work with nature, instead of against it.”