With an available water supply of 188 billion m³ and water extraction of around 32 billion m³ Germany is a water-rich country. Water scarcity is not currently a problem, even though regional shortages caused by low groundwater supplies have to be compensated for by piping water from areas with a surplus. However, recent years have shown that not even Germany is immune to the effects of climate change, such as more frequent flooding and periods of drought.
Protecting groundwater from pollution has always been especially important in Germany because around 65.5 % of the country’s drinking water is taken directly from groundwater supplies. The main causes of chemical pollution in groundwater are high discharges of nitrogen and pesticides, often from agriculture, as well as point-source pollution from residual contamination and landfill sites.
One traditional problem is the high level of pollution of lakes and rivers with nutrients and other substances, and use-related hydro-morphological changes which threaten the natural functions of water-bodies. Nutrients encourage algal growth, which in turn has a number of negative effects on water-bodies. Heavy algal growth results in oxygen shortages that can kill fish. It also makes it more difficult to purify drinking water and can cause allergic reactions for bathers.
To assess the condition of the groundwater, surface and coastal waters, they are monitored regularly as part of national and international programmes. The monitoring programmes carried out by the Länder and the river-basin commissions record not only biological parameters but also chemical properties such as nutrients, heavy metals and organic micro-pollutants, as well as hydro-morphological characteristics following changes to the structure of water-bodies, for example because of shipping, hydroelectric power or flood protection.