A study entitled ‘Four billion people facing severe water scarcity’ published in the Science Advances journal on 12 February 2016 has painted a stark picture regarding the scarcity of fresh water around the world. According to the authors Mesfin Mekonnen and Arjen Hoekstra from the University of Twente in the Netherlands, these four billion are made up of people who have faced scarcity for at least 1 month per year since 1996. Half of these people are in India and China, and more than 100 million of them live in Bangladesh, the United States, Pakistan and Nigeria respectively. Half a billion people have faced year-round severe water scarcity over the last two decades. Of these half a billion people that face severe water scarcity all year round, 180 million live in India, 73 million live in Pakistan, 27 million live in Egypt, 20 million live in Mexico and Saudi Arabia and 18 million live in Yemen.

Over the last few decades, increasing water demand has been threatening sustainable development around the world. The World Economic Forum ranks water as the most significant global risk in terms of potential impact in its latest annual risk report which describes the increasing global population, higher living standards, changes in consumption patterns and expansion of irrigated agriculture as the main drivers for rising water demand.

Spatial and temporal variations in global water demand and availability are significant. Year-round water scarcity is currently a reality in the Amazon basin, Central Africa (e.g. Congo Basin), Sumatra, Borneo, New Guinea, and in the northern forested and subarctic parts of North America, Europe and Asia. At higher latitudes in the western United States, Southern Europe, Turkey, Central Asia and Northern China, many areas experience moderate to severe water scarcity in spring and summer.

According to the study, areas of high population density (e.g. Greater London), with irrigated agriculture (e.g. the high plains in the United States) or with both (e.g. India, eastern China) tend to experience high water scarcity. Of the world’s deserts, water scarcity is worst in the Arabian Desert due to higher population and irrigation densities. In many of the world’s river basins, water consumption is highest when availability is lowest. The Ganges basin in India, the Limpopo basin in Southern Africa and the Murray-Darling basin are examples of this countercyclical pattern.

Rigorous water scarcity assessments can facilitate the development of water scarcity response strategies

The ‘Four billion people facing severe water scarcity’ study concludes that maintaining sufficient catchment water levels in the face of increasing water demand will be one of the most difficult yet important challenges of this century. Without sufficient water catchment levels, agricultural and fishing industries are potentially vulnerable to collapse in the longer term as a result of reductions in rainfall, groundwater flows and runoff respectively. Rigorous water scarcity assessments can facilitate the development of water scarcity response strategies by Governments, companies and investors around the world. These strategies will need to be robust enough to address the realities of changing climates and to address the more typical challenges that Governments, companies as investors face (e.g. innovative legislation, policies and procedures). The efficiency of water use for crops and in rain fed agriculture will need to increase. Governments and companies will also need to prepare water footprint benchmarks based on the best available technology and practice. Assessing the sustainability of the water footprint along product supply chains will also become increasingly important for investors.

Read the ‘Four billion people facing severe water scarcity’ study here

This study prompts me to wonder why environmental issues such as this struggle to get attention from some Governments. The study clearly shows that severe water scarcity affects both developing and developed countries, and therefore nothing less than well planned collaborative actions will suffice in order to ensure that water scarcity can be fought without disadvantaging developing counties. Investors are increasingly factoring environmental sustainability into their purchasing decisions. It therefore makes perfect sense to me that an assessment of water footprints at all stages of supply chains and water scarcity response strategies will become more important in investment decisions. With four billion people around the world facing severe water scarcity, it is clear that Governments, companies, investors and citizens will all have to play their part in maximising the efficiency of the water they use each day.