Coming to Grips with Water Security in the Face of Climate Change

Collecting rainwater data on the farm. Tana River watershed, Kenya. 30 November 2016. ©CIAT/ Georgina Smith


In a landmark study published a decade ago, the International Water Management Institute (IWMI) suggested that under likely scenarios the world’s freshwater supplies should be adequate to meet future demands from agriculture, industry and other sectors.1 A lot has happened since then that makes it difficult today to frame this essentially accurate conclusion in such optimistic terms. It is clear now that, without significant improvement in water management, we can no longer assure sustainable development in the face of climate change and related pressures.

Water Worries

Water crises are, in fact, the single most worrying global issue on the minds of leaders surveyed recently by the World Economic Forum.2 Moreover, of the top five concerns cited, four centre on or are directly linked to water, including the “failure of climate change mitigation and adaptation,” which occupied second place.3 Within the last few years, it has become a truism of work on adaptation that climate change impacts will weigh on societies, economies and the environment primarily through water.

What combination of factors accounts for such a pronounced shift in perspective over the course of just 10 years? A central issue is the rising concern about growing water scarcity relative to demand, driven by rapid population growth, urbanization and economic development. Climate change will compound the scarcity challenge, because higher temperatures will boost rates of evaporation from both soils and water surfaces, increase crop water requirements and raise demand for cooling water necessary to generate the energy that consumers will demand in response to higher temperatures.

The outlook is especially ominous for the world’s vast dry areas, which may be considered the front lines of climate change adaptation. Streamflow declines of more than 50 per cent are “confidently predicted” for these areas, as a result of lower rainfall.4 This will also reduce infiltration of water into aquifers, threatening communities that are highly dependent on groundwater, which is inherently difficult to monitor and manage.

Of particular concern are many poor, agrarian communities in arid regions of sub-Saharan Africa and South Asia, where high rates of rural poverty and low levels of adaptive capacity leave people highly vulnerable to the effects of reduced water availability. Similarly, in many fragile regions of the Middle East and North Africa, climate change is predicted to significantly worsen water scarcity, which could act as a stressor compounding the risks of conflict and migration.5

The Dual Challenge of Water Security

Heightened concern about water scarcity oversimplifies the challenge, however. Climate change will give rise not only to reduced water availability in many places but also to increasingly variable and unpredictable water supplies. More frequent and severe droughts and floods, with dire consequences for rich nations and poor, have already started to drive this lesson home by wreaking havoc on livelihoods and traditional patterns of production.

It is increasingly clear that water security should be the focus of our efforts. The challenge is not only to ensure that there is enough water but to manage it effectively when there is too much water in the wrong place and at the wrong time or if it is of dangerous quality. Our dual aim must be to harness the productive potential of water, while reining in its destructive power. We must first ensure that the quantity and quality of water are sufficient to meet both human needs and environmental demands, and, secondly, that water-related risks to societies, economies and ecosystems are kept within manageable limits.

Unfortunately, actions are lagging behind increased awareness of water-related risks and their implications for sustainable growth. As a result, there is a danger that measures to improve water management will fall far short of the challenge. The International Decade for Action, “Water for Sustainable Development”, 2018-2028, declared by the United Nations General Assembly, is an opportunity to bring national and international efforts to bear on the enduring challenge of water security.

Recent experience in many countries suggests there is a viable way forward to enhanced resilience and sustainable growth in the face of increasing water scarcity and climate change. Getting there requires rapid advances along three parallel tracks to water security, involving increased investment in information, infrastructure and institutions.

An Eye on Information and Data

Growing water scarcity makes it essential to know where water is and is not available, and how it is being used. To this end, IWMI and its partners have developed and widely applied an approach for “water accounting”.6 This helps determine a sustainable water balance, thus providing an evidence base for equitable and transparent water governance. Using standardized data collection and quality standards, the approach integrates hydrological processes with land use, as well as water flows and consumption across entire river basins.

We also need to be able to predict and prepare for water-related risks and extremes. Given the likelihood of increasing variability in water supplies, countries need powerful information tools to assess and monitor these risks. South Asia is a region of particular importance, as it has the world’s greatest concentration of water-related hazards. Recent analysis of risk exposure in the region shows that some 750 million people—more than 45 per cent of the entire population—were affected by climate risks in the decade after 2000.7

In order for local and national authorities to mitigate the impacts of these hazards equitably and effectively, they need ready access to near real-time data on moisture conditions. In an effort to provide such information, IWMI undertook the development of the South Asia Drought Monitoring System (SADMS) several years ago.8 The online system provides a weekly map of drought conditions in the region, using state-of-the-art indices and freely available satellite imagery to provide local assessments of drought impacts on agriculture. IWMI researchers are also working with colleagues at the Indian Council of Agricultural Research (ICAR) to pilot a drought early warning system for the southern States of India. Comprising multiple indices based on temperature, rainfall and wind-speed data, the system is designed to provide a forecast of changes every 16 days in soil moisture, which serves as an indicator of drought potential.

An Open Mind on Infrastructure

Lowering the risks associated with increasingly variable water availability will require more natural and built infrastructure to store and deliver water, and to protect against drought and flood.

The conventional approach for generating greater benefits from water while limiting its hazards has historically centred on investment in built or “grey” infrastructure, such as dams, dikes and reservoirs. A potential drawback is that major dam construction can exact unacceptably high costs in terms of its negative impacts on water-dependent ecosystem services and on the people, especially in poor rural communities, whose livelihoods are closely tied to these services.

In recent years, research for development across Africa and Asia has stressed the potential of natural or “green” infrastructure as a complementary option for bolstering climate change adaptation and sustainable growth. Wetlands, lakes, aquifers and even soils can all be used for water storage, while floodplains, wetlands and mangroves can serve the purposes of flood protection. One technique, referred to as managed aquifer recharge, can contribute to both purposes. IWMI is piloting efforts in India to help attenuate floods by capturing excess water in the monsoon season, using that water to strategically recharge aquifers, and then making it available for irrigation in the dry season.9

Nature-based solutions can at the same time sustain ecosystems and the natural heritage, enhancing aesthetic and recreational values. This emphasis on nature-based solutions recognizes that grey infrastructure by itself cannot achieve both development and environmental goals in the face of climate change and other pressures.

To make good on the promise of a mixed approach requires that we build a solid case for investment in portfolios that encompass both built and natural infrastructure, derived from science-based assessments of their social, economic and environmental value. This is the central aim of a project focused on the Tana River Basin in Kenya and the Volta River Basin in West Africa under the leadership of the International Union for Conservation of Nature (IUCN). Research conducted by IWMI and other project partners has demonstrated that natural infrastructure in these basins offers multiple benefits and has determined the economic value of these, accruing to hundreds of thousands of people.10

World Water Day 2018, with its “Nature for Water” theme, will no doubt draw further attention to nature-based solutions for addressing water challenges.

A Commitment to Institutional Innovation

Adapting to increased water scarcity and variability related to climate change will place heavy demands on institutions, broadly defined as the organizations, policies, norms, practices and incentives governing water. Better water governance to meet social, economic and environmental goals will be a core challenge for institutions throughout the International Decade for Action, “Water for Sustainable Development”, 2018-2028.

Institutional innovations will be needed to realign historic water allocations and management practices with increased water demands, changing economies and demographics, as well as evolving societal priorities. Institutions will need to be more flexible and adaptive, so they can respond successfully to the uncertainties that climate change will bring. They will also need to be more transparent and participatory if they are to ensure the inclusion of disadvantaged groups and women.

A New Sense of Urgency

The last decade has seen rising concerns regarding water-related threats to sustainable growth, and this is, of course, a welcome shift. Our challenge now is to respond effectively to mounting water worries through science-based initiatives that can ensure there is enough water, mindfully managed and equitably allocated, during the years to come. This is the spirit of the International Decade for Action, “Water for Sustainable Development”, which lends new urgency to our efforts to manage water more wisely.    



  1. David Molden, ed., Water for Food, Water for Life: A Comprehensive Assessment of Water Management in Agriculture. Summary (London, UK, Earthscan and Colombo, Sri Lanka, International Water Management Institute (IWMI), 2007). Available from
  2. World Economic Forum, The Global Risks Report 2016, 11th ed. (Geneva, Switzerland, 2016). Available from
  3. Ibid., p. 6.
  4. Maarten de Wit and Jacek Stankiewicz, “Changes in surface water supply across Africa with predicted climate change”, Science, vol. 311, No. 5769 (31 March 2006), pp. 1917-1921. Available from
  5. Claudia W. Sadoff and others, Securing Water, Sustaining Growth: Report of the GWP/OECD Task Force on Water Security and Sustainable Growth (Oxford, UK., University of Oxford, 2015). Available from
  6. International Water Management Institute (IWMI) and others, Water Accounting. Independent estimates of water flows, fluxes, stocks, consumption, and services. Available from (accessed 1 February 2018).
  7. Giriraj Amarnath and others, Mapping Multiple Climate-related Hazards in South Asia. IWMI Research Report 170 (Colombo, Sri Lanka, International Water Management Institute (IWMI), 2017), p. vii. Available from
  8. International Water Management Institute, South Asia Drought Monitoring System (SADMS). Available from (accessed 1 February 2018).
  9. Paul Pavelic and others, Controlling Floods and Droughts through Underground Storage: From Concept to Pilot Implementation in the Ganges River Basin. IWMI Research Report 165 (Colombo, Sri Lanka, International Water Management Institute (IWMI), 2015). Available from
  10.  CGIAR Research Program on Water, Land and Ecosystems (WLE), Re-conceptualizing Dam Design and Management for Enhanced Water and Food Security (Colombo, Sri Lanka, International Water Management Institute (IWMI), 2017), CGIAR Research Program on Water, Land and Ecosystems (WLE), WLE Towards Sustainable Intensification: Insights and Solutions, Brief 3. Available from