Water is vital for human beings, animals and plants and concurrently one of the most important natural resources. Water abounds on the earth as some 70 percent of its surface is covered with water estimated at a volume of approximately 1.4 billion cubic kilometres. However, most of it is salty, and only around 2.5 percent of the global water resources (about 35 million cubic kilometres) consists of fresh water.
Only a fraction of the fresh water can be used for drinking water purposes though, since about 69 percent are bound as snow and ice mainly in the Antarctica and in Greenland. Over 30 percent (about 10.5 million cubic kilometres) is stored as groundwater beneath the earth’s surface - the most important available fresh water resource. Lakes, artificial lakes and rivers account for far less than a half percent of the fresh water reserves.
Groundwater is the most widespread and highly used resource. It is of inestimable value to the inhabitants of dry regions, being the only reliable water resource they have. The yearly consumption of groundwater world-wide is assumed to 1000 cubic kilometres, and the global groundwater recharge at 12,700 cubic kilometres per year. In many countries the drinking water is mainly tapped from groundwater, in Germany more than 70 percent. In countries such as Denmark, Lithuania and Austria, groundwater is nearly the only source for public water supply.
Around 1.5 billion people on earth are supplied with groundwater. The importance of groundwater will grow considerably in the future, as it is a safe and qualitatively high drinking water resource. If it is used reasonably and sustainably, it can provide an important contribution in solving regional water crises on earth.
BGR advises the ministries of the German Federal Government on all questions concerning groundwater exploration, quantitative and qualitative assessment of groundwater resources and their use, groundwater protection and geothermal use of groundwater. Sustainable groundwater management is a principal focus in our activities for development cooperation.