Sylvenstein Dam is an earthen and rockfilled

embankment dam An embankment dam is a large artificial dam. It is typically created by the placement and compaction of a complex semi-plastic mound of various compositions of soil or rock. It has a semi-pervious waterproof natural covering for its surface ...

in the

Isar The Isar () is a river in Austria and in Bavaria, Germany. Its source is in the Karwendel mountain range of the Alps. The Isar river enters Germany near Mittenwald and flows through Krün, Wallgau, Bad Tölz, Munich, and Landshut before reaching ...

valley, in the alpine part of

Upper Bavaria Upper Bavaria (, ; ) is one of the seven administrative regions of Bavaria, Germany. Geography Upper Bavaria is located in the southern portion of Bavaria, and is centered on the city of Munich, both state capital and seat of the district gove ...

, Germany which impounds the multipurpose Sylvenstein Reservoir (). It was built with the primary aim of flood protection for the region. However, it also serves as a water reservoir for when water quality is lower downstream as well as a reservoir for

hydroelectric Hydroelectricity, or hydroelectric power, is Electricity generation, electricity generated from hydropower (water power). Hydropower supplies 15% of the world's electricity, almost 4,210 TWh in 2023, which is more than all other Renewable energ ...

power.

Construction

In the 1920s, several

hydropower Hydropower (from Ancient Greek -, "water"), also known as water power or water energy, is the use of falling or fast-running water to Electricity generation, produce electricity or to power machines. This is achieved by energy transformation, ...

plants were built in the

tributary A tributary, or an ''affluent'', is a stream or river that flows into a larger stream (''main stem'' or ''"parent"''), river, or a lake. A tributary does not flow directly into a sea or ocean. Tributaries, and the main stem river into which they ...

of the upper Isar River such as ones at the Achensee and Lake Walchen Power Plant. Therefore, the river ran nearly dry during the dry season, and the low water flow affected the town of

Bad Tölz Bad Tölz (; Bavarian: ''Däiz'') is a town in Bavaria, Germany and the administrative center of the Bad Tölz-Wolfratshausen district. History Archaeology has shown continuous occupation of the site of Bad Tölz since the retreat of the gla ...

. A reservoir was established to ensure a minimum water level in the river. During the dry season, a volumetric flow of 4 cubic metres per second is released to prevent the Isar from running dry. Additionally, the reservoir provides

flood control Flood management or flood control are methods used to reduce or prevent the detrimental effects of flood waters. Flooding can be caused by a mix of both natural processes, such as extreme weather upstream, and human changes to waterbodies and ru ...

for the Isar River between

and Munich. The dam is high and long. It was built between 1954 and 1959. Since 1959, the water has also been used to operate a hydropower plant of 3.2 MW. The plant was upgraded in 2000 with new turbines to generate 3.8 MW. The damn has a core of processed

moraine A moraine is any accumulation of unconsolidated debris (regolith and Rock (geology), rock), sometimes referred to as glacial till, that occurs in both currently and formerly glaciated regions, and that has been previously carried along by a gla ...

History

During the 2005 European floods, the reservoir's maximum capacity was reached. Consequently, excess water was released into the Isar River. Without the dam construction, the flooding in 2005 would have been even more severe than it actually was. Sylvensteinspeicher 100708

A small village named Fall was flooded in 1959. The Faller-Klamm-Brücke connects road traffic to the North ( Bundesstraße 307).

References

External links

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Information and photographs
{{Authority control Dams in Bavaria Lakes of Bavaria Hydroelectric power stations in Germany Dams completed in 1959 Bad Tölz-Wolfratshausen