In Northern Germany the primary source for drinking water supply is groundwater from Quaternary and Tertiary Aquifers. At 2000 around 25 % of North German aquifers show inland salinization (upconing deeper saltwaters) and about 5 % seawaetr intrusion. About Km coastal region (roughly measured) at the North Sea are corcerned plus several barrier islands but also the metropolitan area of Hamburg.