3.2 WATER 62 There are more than 326 million trillion gallons of water on Earth. Less than 3% of all this water is freshwater and more than two-thirds is locked up in ice caps and glaciers. SDG 6: Ensuring access to drinking water, sanitation and hygiene by 2030 would save 829,000 people annually. aquifer: falda acquifera borehole: pozzo dam: diga to deplete: esaurire ditch: fosso freshwater: acqua dolce glacier: ghiacciaio groundwater: acqua sotterranea ice cap: calotta glaciale moisture: umidit orchard: frutteto reservoir: bacino WATER RESOURCES About 70% of the Earth s surface is covered by water, and the oceans hold about 96.5% of it all. However, water also exists in the air as water vapour, in rivers and lakes, in ice caps and glaciers , in the ground as soil moisture and aquifers, and even in humans and animals. Even though the majority of the water on the Earth s surface is saline, freshwater resources, such as the surface water of streams, rivers and lakes, and groundwater, provide living beings with most of the water they need, both for human consumption and for crop irrigation. Supplied from boreholes, dams, reservoirs, rivers and lakes, water is distributed to fields, orchards, vineyards or other cultivated areas by means of canals, ditches or pipes. Water shortage The negative effects of rapid population growth, urbanisation, climate change impacts, and lifestyle changes are compromising water quality, quantity, accessibility and availability. In the last 100 years, water consumption has grown 6 times, and it is foreseen the world s demand for water will rise 40% over the next decades. Currently, 1.2 billion people live without purified drinking water and thousands die every day from diseases directly attributable to unsafe water, inadequate sanitation and poor hygiene practices . Renewable or non-renewable Resources are called renewable if they can be replenished at reasonable rates so that humans will not run out of them. Therefore, water is renewable because it is recycled in reasonably short periods of time: it leaves the Earth, but it also re-enters it, falling back as rain or snow and being deposited in rivers, lakes, and oceans. However, only 2.5% out of the total volume of water is freshwater and is being used at a much larger rate than it can be replenished. Therefore, water can also be considered as non-renewable and water conservation is crucial. Monitoring water consumption Few countries measure the quality of groundwater or the rate at which it is being exploited. Monitoring is being improved in Europe and India, but remains minimal in many developing countries, and is deteriorating in many industrialised ones. This makes it hard to manage underground water resources sustainably, and if these are depleted, the consequences will be rising temperatures, drying land, drinking-water shortage, food shortage and famine. 126 Soil, water and plantS