Freshwater scarcity will be a difficult and important challenge to overcome this century. Dam construction is seen as one solution to help increase water supplies, with the World Bank predicting an unprecedented growth in the number of dams. However, in order to protect against water-related shocks and balance competing priorities, all-encompassing global water management must become paramount. Suzanne Pritchard reports.

Freshwater scarcity is increasingly perceived as a global systemic risk. The authors of a recent report from the University of Twente in the Netherlands have labelled it as a threat to “the sustainable development of human society”, while the World Economic Forum lists water crises as the largest global risk in terms of potential impact.

At a global level and on an annual basis, enough fresh water is available to meet increasing human demands. However, as Dutch authors Mekonnen and Hoekstra state in their report, the problems lies with the fact that: “spatial and temporal variations of water demand and availability are large, leading to water scarcity in several parts of the world during specific times of the year. The essence of global water scarcity is the geographic and temporal mismatch between freshwater demand and availability.”

Through their calculations the authors found that 4B people, two-thirds of the world’s population, experience severe water scarcity during at least part of the year. And this, Mekonnen and Hoekstra claim, implies that the situation is worse than suggested by previous studies which give estimates between 1.7-3.1B people.

High and dry

An accumulation of evidence suggests that the problem of water allocation will become increasingly acute for governments around the globe. Recent research by the World Bank says that water scarcity, exacerbated by climate change, could have a detrimental regional effect on GDP, prompt migration, and spark conflict.

Published in May 2016, High and Dry: Climate Change, Water and the Economy, says the future will be thirsty. The combined effects of growing populations, rising incomes, and expanding cities will see demand for water rising exponentially, while supply becomes more erratic and uncertain under climate change.

“Overall,” the Bank says, “barring significant increases in water efficiency (especially in agriculture), the world may face a shortfall in water availability of approximately 2700Bm3 by 2030, with demand exceeding current sustainable water supplies by 40%.”

Unless action is taken soon, the report warns, water will become scarce in regions where it is currently abundant – such as Central Africa and East Asia – and scarcity will greatly worsen in regions where water is already in short supply – such as the Middle East and the Sahel in Africa.

“Water scarcity is a major threat to economic growth and stability around the world, and climate change is making the problem worse,” said World Bank President Jim Yong Kim. “If countries do not take action to better manage water resources, our analysis shows that some regions with large populations could be living with long periods of negative economic growth. But countries can enact policies now that will help them manage water sustainably for the years ahead.”

Thirsty business

Economic growth is described as being a surprisingly thirsty business. “Water is a vital factor of production,” the World Bank states, “so diminishing water supplies can translate into slower growth that clouds economic prospects.” This means that some affected regions could see their growth rates decline by as much as 6% of GDP by 2050, due to water-related impacts on agriculture, health and income. Climate change will increase water-related shocks on top of already demanding trends in water use. Reduced freshwater availability and competition from other uses, such as energy and agriculture, could reduce water in cities by as much as two thirds by 2050, compared to 2015 levels.

Bad water management policies can exacerbate the adverse growth impacts of climate change, while good policies can go a long way towards neutralising them, the Bank continues. The economic modelling utilised in the report sees some regions stand to see growth accelerate as much as 6% with better water resource management. However the impacts of water mismanagement are felt disproportionately by the poor, who are more likely to rely on rain-fed agriculture to feed their families, live on the most marginal lands, and are most at risk from contaminated water. Ensuring a sufficient and constant supply of water under increasing scarcity will be essential to achieving global poverty alleviation goals.

“Water is the common currency which links nearly every sustainable development goal, and it will be a critical determinant of success,” the authors of High and Dry state.

Water insecurity also has the potential to multiply the risk of conflict. Food price spikes caused by droughts can inflame latent conflicts and drive migration. Where economic growth is impacted by rainfall, episodes of droughts and floods have generated waves of migration and spikes in violence within countries.

“There is a silver lining,” according to the report’s author and a World Bank Lead Economist Richard Damania. “When governments respond to water shortages by boosting efficiency and allocating even 25% of water to more highly-valued uses, losses decline dramatically and for some regions may even vanish. Improved water stewardship pays high economic dividends.”

Unprecedented increase

In the world’s extremely dry regions, more far-reaching policies are needed to avoid inefficient water use. Stronger policies and reforms are needed to cope with deepening climate stresses, the World Bank report says. It outlines policies and investments that can help lead countries to more water secure and climate-resilient economies. This includes better planning for water resource allocation, adoption of incentives to increase water efficiency, and investments in infrastructure for more secure water supplies and availability.

Where appropriate the Bank says that water supply and availability need to expand, and include investment in storage infrastructure such as dams. Globally, the stage is described as being set for “a tremendous and unprecedented” increase in the number of dams. Numbers are expected to swell by 16% by 2030, and storage volume is expected to increase by about 40%. However the Bank does offer a word of caution: “Historically, when supply is increased without corresponding safeguards to manage use, demand rises to meet the new level of supply, resulting in a higher level of water dependence in often arid areas. To be effective,” it says, “these interventions must be accompanied by policies to promote water efficiency and improve water allocation across sectors.”

In order to meet these challenges, the World Bank stresses that all stakeholders in the global water sector, including governments, the private sector, and civil society, must join together to emphasise that every individual water user has a part to play.

Complex phenomenon

Such advice has been heeded by the Department for Environment, Food and Rural Affairs (DEFRA) in England. DEFRA has been establishing government plans to ensure the long term resilience of the water sector in response to pressures of climate change and a growing population. The department says that to meet the challenges of scarcity, the water industry may need to develop new and nationally significant water supply infrastructure.

In addition, independent civil engineering and environmental hydraulics organisation HR Wallingford, has been working with the Environment Agency (EA). Senior hydrologist Ralph Ledbetter has sought to gain an understanding of water supply resilience to drought, and to develop integrated hydrology and water resource models of large UK catchments for water supply planning purposes.

“Drought is a complex phenomenon whose occurrence and predictability, even today, is not fully understood by meteorologists, climatologists and hydrologists,” Ledbetter explains. He says that water companies need to understand how their systems will perform during periods of drought, but in order to see the bigger picture for effective drought planning, they need to look beyond historical records.

Drought events are rare and their characteristics are both spatially and temporally variable between different drought events. Planning in response to historical record alone does not reflect the fact that droughts could occur in the future with different characteristics to those that we have already experienced. The concern therefore, HR Wallingford’s hydrologist says, is that a water supply system may appear robust to the historical events to which it is designed, but it may not perform to the same standards when exposed to a previously unseen drought.

Ledbetter gives details about methods and evidence sources that exist for creating droughts with different characteristics from those in the historical record. Understanding the differences between methods can help to identify which is most suitable for testing a specific water supply system. Such testing allows a water supply planner to understand whether their system would be robust when exposed to various drought events: an important consideration when freshwater scarcity is looming on the horizon.

Global summit

Water scarcity concerns are also being addressed on the other side of the world. As Gary Jones, Chief Executive of the Australian Water Partnership, says: “Drought management is not just about new infrastructure and technologies, but also about demand management and effective water allocation policy. It is about building systems that are broadly resilient to drought and scarcity, managing demand as well as improving supply.”

Together with the International Water Association (IWA), the Australian Water Partnership will convene government and business leaders, NGOs, scientists and international organisations to a global summit on water scarcity and drought. Set to take place on 10 October 2016 in Queensland, Australia, the summit will be held in connection with the World Water Congress and will focus on:

  • Establishing portfolios of water supply and demand management.
  • Strengthening mechanisms to measure and exchange on water scarcity and drought.
  • Mobilising public and private investments in water management.

Government level participation is also expected from the most impacted countries: Australia, Botswana, Brazil, China, India, Iran, Japan, Jordan, Korea, Mexico, Morocco, Saudi Arabia, Senegal, South Africa and the US.

“Cities, industries, agriculture and the environment are seriously impaired by water scarcity. Cities around the world have literally run out of water this year, resulting in major havoc and costs for citizens, business and government,” says Dr Ger Bergkamp, Executive Director of the International Water Association. “The world needs decisive action, a modern day plan for global water scarcity. We need all stakeholders to agree on a clear agenda and begin to manage water more wisely,” he added.

Water Panel

World Bank Group President, Jim Yong Kim, agrees that at a time of unprecedented water challenges, global action, strong leadership and commitment are required. In a collaborative effort with United Nations Secretary General Ban Ki-moon, Kim recently announced the appointment of ten heads of state and government to the High Level Panel on Water. Launched at the World Economic Forum, the panel has been tasked with providing the leadership required to champion comprehensive, inclusive and collaborative action on water resources. Appointed panel members include representatives from:

  • Mauritius
  • Mexico
  • Australia
  • Bangladesh
  • Hungary
  • Jordan
  • Netherlands
  • Tajikistan
  • Republic of Korea
  • Peru

“Ensuring water and sanitation for all is crucial for reducing poverty and achieving Sustainable Development Goals,” UN Secretary General Ban ki-Moon added. He urged all partners to mobilise behind these goals with political, financial and technological support.

Global water challenge

“While water scarcity and drought will increasingly pose major challenges to society, managing these situations can be turned into a major opportunity for development, business and communities,” Bergkamp said, adding that leadership and a pro-active approach which engages a wide range of stakeholders throughout society will be required.

“We must all become advocates for a more sustainable water future,” Richard Damania from the World Bank concludes. “We must raise awareness to ensure all stakeholders understand their part in the global water challenge, and are empowered to play a role in addressing it.”



  • Four billion people facing severe water scarcity by Mesfin M. Mekonnen and Arjen Y. Hoekstra. Science Advances 12 Feb 2016: Vol. 2, no. 2, e1500323. DOI: 10.1126/sciadv.1500323
  • High and Dry: Climate Change, Water, and the Economy. World Bank. 2016. World Bank, Washington, DC. License: Creative Commons Attribution CC BY 3.0 IGO.
  • Water supply planning and drought by Dr Ralph Ledbetter. Courtesy of HR Wallingford. Posted 3 February 2016.
  • International Water Association – Email:
  • Australian Water Partnership – Email: