Written by António Vale and Jurgita Lekaviciute.
Globally, it has been estimated that four billion people are facing severe water scarcity. While the situation is not yet critical in Europe, water stress is already a serious issue and climate change is expected to make it worse in the future. What is the extent of the problem, and what solutions are available to avoid running out of water?
The European Union (EU) has been affected by episodes of severe drought over the past decade, particularly in 2022. Measures of water stress show it affects 20 % of European territory and 30 % of the European population yearly on average. A closer look at its geographical distribution sees southern Europe as a hotspot, but also shows important pressure on river basins in western and central Europe.
The overall trend in the EU is positive, withdrawals of water having fallen by 15 % between 2000 and 2019. Three quarters of water extraction comes from surface waters, the remainder from groundwater. When it comes to drinking water, however, a full 65 % comes from underground sources. With slow natural processes of aquifer recharge and high sensitivity to pollution, the latter are a particularly vulnerable source. Some 29 % of total groundwater body area in the EU is of poor quantitative or chemical status. Satellite measurements also paint a general picture of depleting groundwater levels in some areas. Agriculture accounts for about 30 % of the water extracted, mostly concentrated in a few Member States. Cooling of thermal power plants accounts for a similar share: municipal water supply for about one quarter, other industry and services for the remainder. This picture is complicated by the fact that much of the water extracted is eventually returned to the environment, although often with added impurities or pollutants, and for some uses the difference between extraction and consumption can be very large. Finally, there are also non-productive losses, such as leaks in the drinking water distribution network that reach 40 % or higher in some EU Member States.
Climate change is set to worsen these trends, its impact showing a north-south divide. Models predict that temperatures will increase across the board but, while drought frequency is expected to increase, northern Europe is predicted to see higher rainfall, although with more extreme precipitation. One final important impact is changes to river flows, which will see a decrease in summer flows in most of Europe.
Potential impacts and developments
It is clear that urgent action is required, with solutions coupling an increase in availability of good quality water with a decrease in consumption. Geography will be a central factor in deploying solutions, in terms not only of the current situation and its expected evolution, but also of the level of the local water cycle.
With the most obvious sources already tapped, options to increase supply look to the sea and the atmosphere. Desalination is a relatively old idea that comes with significant drawbacks in energy use and the environmental impact of brine waste. New technological developments may help make it more appealing, but for the moment, it mostly remains a solution for when there is no alternative. Atmospheric water generation technology is another field traditionally held back by high-energy requirements. While recently seeing much progress, with some promising solutions using little or no energy, it is however unlikely to have significant quantitative impact soon. A few other outside the box ideas have also been proposed, from cloud seeding to iceberg harvesting.
Given the difficulty in increasing supply, addressing the issue will necessarily involve recycling and reusing water, as well as reducing consumption. Part of the solution may involve better reuse of wastewater, as is already the case in Singapore, for example. Water storage will grow in importance, as climate change brings higher seasonal variation and more frequent extreme events. Managed aquifer recharge may not only help with this, it could also help address unsustainable groundwater extraction. Preventing leaks in the distribution network and reducing evaporation in reservoirs could also minimise losses. Better use could be made of rainwater, at both urban and domestic levels. in general, cities could adapt more effectively by means of practices such as water sensitive urban design. At domestic level, in addition to water reuse systems, smart meters and other digital tools can help with water conservation.
As one of the major users of water, agriculture will play a large role: solutions may include adapting crop types to changing water availability, or developing new strains that are more resistant to dry conditions. More efficient irrigation mechanisms and better reuse of wastewater for irrigation may also help to conserve water. The case of the other major user, the electricity sector, is more complex: a context of severe water scarcity may bring a shift to closed cooling systems in thermal power plants; these require less water but lead to higher water consumption. The overall situation, however, is set to change as wind and solar power, which require little water for operation, become more prevalent. Elsewhere in industry, the solution may involve recycling water, an idea currently being explored by the chip manufacturing industry. Although it is difficult to determine water’s true value, market mechanisms may help conserve water via price signals. However, water is a basic necessity, and reflecting this in its cost is fraught with difficulty.
Nevertheless, a large part of the solution may lie in going back to nature. Grey or hard infrastructure has so far dominated water resource management, but the focus is now shifting to nature-based solutions (NBS). Such NBS for water management involve the use of ecosystem services to improve water quantity and quality and increase resilience to climate change. Ecosystems regulate water supply, moderate water quality and mitigate extreme climate events. For example, NBS can help maintain water supplies by increasing the infiltration and storage capacity of wetlands and soils and recharging aquifers. They can also mitigate droughts by releasing water from natural storage features and extend the life of reservoirs by reducing siltation. To regulate water quality, NBS can help treat polluted water, protect groundwater from contamination by removing sediments and pollutants, and improve wastewater quality. To mitigate extreme climate events, NBS can help increase water storage capacity in watersheds and urban areas, thereby reducing downstream flooding, slowing the flow of floodwaters, and reducing crop vulnerability to drought. Despite its growing use, direct investment in NBS still represents less than 1 % of total investment in water resource infrastructure and management worldwide.
The Water Framework Directive (WFD) is the key European tool to tackle water stress and ensure sustainable water use, together with a series of other water laws. However, implementation is slow and integration of environmental objectives into sectoral policies is insufficient – as water use is transversal to many sectors, other legislation also has a relevant impact. Here, the EU common agricultural policy (CAP) plays a particularly important role. A recent European Court of Auditors report found inconsistent alignment of the CAP with water policy, with many exemptions granted for agricultural water use. It recommends better justifying such exemptions, linking CAP payments to sustainable water use and ensuring EU-funded projects help achieve WFD objectives. The Green Deal also has important ramifications: promoting wind and solar power leads to reduced water use in the energy sector; it may also be key in promoting the adoption of NBS. In addition, water policy would need to account for the geographical diversity of challenges, as well as the asymmetric impacts and increased seasonality brought by climate change.
Research and innovation will continue to play an important role in finding innovative solutions, and will help with the shift from a ‘silo’ approach to a collaborative one (an example is the launch of a new knowledge and innovation community on water). There are also initiatives from the European Parliament and the European Economic and Social Committee, calling for an ‘EU Blue Deal’ within the European Commission’s next mandate.
Finally, it is important to give water an appropriate economic value, and value it as an asset that generates functions and services for human wellbeing. Discussions on water economics have just begun, including through initiatives such as the Global Commission on the Economics of Water.
Read this ‘at a glance’ on ‘What if Europe ran out of water?‘ in the Think Tank pages of the European Parliament.
Listen to podcast ‘What if Europe ran out of water?‘ on YouTube.