Hydrogeological Map of Austria 1:500.000
Hydrogeological maps take an intermediary position between geological and hydrological maps.
Although Austria is sometimes referred to as the "water reservoir of Europe", this is not valid for the whole country as well. The Northern Limestone Alps, which run throughout Austria, are the areas with the most abundant water resources. Here are also great wells which often have highly variable volume fluctuations. This is due to a rich precipitation and the widespread of karstic rocks. Large cities such as Vienna or Innsbruck obtain their water from the Northern Limestone Alps.
Type and location of aquifers determine the supply and availability of groundwater. In Austria, the different types of aquifers display a large variety due to the particular geology of the country. Exact knowledge of them is necessary for their protection.
Areas whose surface consists of crystalline rocks or from clays and marls, generally have a lower groundwater management. These include the Bohemian Massif in the north of Austria, but also large areas in the central Alpine region and the flysch zone in the foothills. Here a precise knowledge of the local situation is needed to ensure the water supply, which is still based on distributed locally (domestic) wells. In places there are vaste areas of carbonate and marble, in turn, have a rich groundwater management. Often, however, deeper drilling will be required to tap ground water bearing rocks.