The springs are safe
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| The underground water-bearing strata are located some 30 to 50 metres below the rail tunnel. As a result of groundwater mitigation, a change in the hydrogeology will be prevented, ensuring that no mineral water can rise. |  The underground water-bearing strata are located some 30 to 50 metres below the rail tunnel. As a result of groundwater mitigation, a change in the hydrogeology will be prevented, ensuring that no mineral water can rise. |
Stuttgart is one of the few metropolises in Europe to have mineral water springs. After Budapest, the capital city of Baden-Württemberg has the second-largest occurrence of mineral water of any city in Europe. In the districts of Bad Cannstatt and Berg, 44 million litres of mineral water spring from twelve wells and several natural mineral water sources into the Neckar every day. Stuttgart’s mineral water deposits in the Upper Muschelkalk (rock strata that date back to the Middle Triassic in Germany) were already known to the Ancient Romans and in the Middle Ages. The mineral water was channelled in 1773 in the course of drilling work at Sulzerrain (near the present spa centre in Cannstatt) in search of salt water which was to be used for salt extraction. As no salt water was found, the mineralised water form the Upper Muschelkalk stratum was used to power an oil mill.
In the mid-19th century, Cannstatt was a flourishing spa town. Today, three major mineral water spas in Berg, Leuze and Bad Cannstatt have taken over its historic heritage and now attract hundreds of thousands of visitors every year. The mineral water springs in Stuttgart are specially protected by law, ensuring that the typical water composition with its carbon dioxide content and the output of these sources are safe over the long term.
Stuttgart’s medicinal springs have been officially recognised since 1964/65. The title of “medicinal water” is granted only to water with hydrochemical properties which have been proved to have a therapeutic effect. The 477-metre deep Hofrat Seyffer spring with Cannstatt thermal salt water has also been officially approved as a medicinal spring since 2003.
Comprehensive survey programme
A comprehensive programme of surveys was already launched in connection with the Stuttgart - Ulm rail project back in 1992, in the course of which the line layout was meticulously investigated, with more than 200 groundwater measuring points. The findings from these analyses served as the basis for expert opinions and hydraulic model calculations, which were then used to develop the concrete plans and concepts for protecting the medicinal springs. The planning permission decisions relating to Stuttgart 21 contain detailed specifications for monitoring water management to protect the medicinal springs
If the project is implemented according to schedule, all the participating experts from the city, Greater Stuttgart Region and Land of Baden-Württemberg rule out the possibility of any long-term deterioration of the groundwater, including the medicinal and mineral water springs, as a result of Stuttgart 21.
Long-term monitoring
The output quantity and quality of the medicinal and mineral water springs have been monitored since 1950. This involves regular measurements and hydrochemical analyses. In 2004, the Environmental Department of the City of Stuttgart optimised the extent of these measurements and drew up a long-term monitoring strategy aimed at
- identifying the spatial and chronological patterns of the spring system.
- supporting management of the springs
- monitoring sustainable use of the springs
- documenting measures to protect the springs
- recognising any changes in the area around the springs
This monitoring process is therefore an instrument for safeguarding the spring system. The Environmental Department is responsible for management of the data, which forms the basis for water management decisions in the city area. It provides an up-to-date and comprehensive picture of the local and regional groundwater situation.