The world is projected to face a 40% global water deficit by 2030 unless we dramatically improve the management of this precious resource. This is the main message of the UN’s World Water Development Report 2015, launched on Friday two days before World Water Day. The planet has never been so thirsty: About 1.2 billion people live in areas where water is physically scarce and 748 million people do not have access to improved sources of drinking water. The water crisis is not one of resource availability, the report stressed. There is enough water to meet the world’s growing needs - but not without dramatically changing the way water is used, managed and shared. At least 50% of the global population uses groundwater resources to satisfy drinking water needs. Groundwater also accounts for 43% of all water used for irrigation. An estimated 20% of the world’s aquifers are being over-exploited, leading to serious consequences such as land subsidence and saltwater intrusion. The report predicts that, by 2050, global water demand will increase by 55%, mainly due to growing urbanisation, climate change and demand from agriculture. The agricultural sector accounts for 70% of global freshwater withdrawals, and more than 90% in some of the world’s poorest countries. According to the report, the intensive and often inefficient use of water for crop irrigation depletes aquifers, reduces river flows, degrades wildlife habitats and has caused salinisation of 20% of the irrigated land area. Water quality faces pressures from pollution through the release of pesticides and chemicals into watercourses and the lack of wastewater treatment in developing countries. Eutrophication of surface water and coastal zones are expected to increase almost everywhere until 2030. The number of lakes with harmful algal blooms will increase by at least 20% until 2050. To make water use more sustainable, agriculture must reduce water losses and increase water productivity (i.e. producing more crop or value per volume of water applied). The UN experts suggest that improvements in ‘crop per drop’ could be realised by adopting agro-ecological methods such as the System of Rice Intensification, which gives plants only the ideal amount of water and keeps the soil temporarily dry instead of continuously flooding rice fields. The report suggests a combination of more stringent regulation and well-targeted subsidies can help reduce water pollution. Water use efficiency could also be improved by rewarding farmers who use efficient irrigation methods. For example, in an arid country like Cyprus, subsidies have led to a major change in farmers’ attitudes towards irrigation techniques and the imposition of water-saving techniques. As the UN prepares to adopt the future Sustainable Development Goals for the time after 2015, the report points to the need to devote an entire goal to water. (ab)