Sylvenstein Dam is an earthen

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 and ...

in the

Isar The Isar is a river in Tyrol, Austria, and Bavaria, Germany, which is not navigable for watercraft above raft size. Its source is in the Karwendel range of the Alps in Tyrol; it enters Germany near Mittenwald and flows through Bad Tölz, ...

valley, in the alpine part of

Upper Bavaria Upper Bavaria (german: Oberbayern, ; ) is one of the seven administrative districts 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 s ...

, Germany which impounds the Sylvenstein Reservoir (german: Sylvensteinspeicher). In the 1920s, several

hydropower Hydropower (from el, ὕδωρ, "water"), also known as water power, is the use of falling or fast-running water to produce electricity or to power machines. This is achieved by converting the gravitational potential or kinetic energy of ...

plants were built in the

tributary A tributary, or affluent, is a stream or river that flows into a larger stream or 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 drain the surrounding drainag ...

of the upper Isar river such as ones at the

Achensee Lake Achen (german: Achensee) is a lake north of Jenbach in Tyrol, Austria. It is the largest lake within the federal state, and has a maximal depth of 133 metres. Together with the Achen Valley it parts the Karwendel mountain range in the west ...

and

Lake Walchen Power Plant The Walchensee Power Plant (german: link=no, Walchenseekraftwerk) is a hydroelectric power station in Bavaria, Germany. It is a storage power station that is fed water from the Walchensee which is then released into the Kochelsee. The install ...

. 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 level of water in the river. During the dry season a

volumetric flow In physics and engineering, in particular fluid dynamics, the volumetric flow rate (also known as volume flow rate, or volume velocity) is the volume of fluid which passes per unit time; usually it is represented by the symbol (sometimes ). I ...

of 4 cubic metres per second is released to prevent the Isar from running dry. Additionally, the reservoir provides

flood control Flood control methods are used to reduce or prevent the detrimental effects of flood waters."Flood Control", MSN Encarta, 2008 (see below: Further reading). Flood relief methods are used to reduce the effects of flood waters or high water level ...

for 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. During the

2005 European floods The 2005 European floods hit mainly Romania, Switzerland, Austria and Germany, as well as several other countries in Central Europe and Eastern Europe during August 2005. The disaster came at a time when Portugal was suffering from intense fores ...

, the maximum capacity of the reservoir 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 Autumn, also known as fall in American English and Canadian English, is one of the four temperate seasons on Earth. Outside the tropics, autumn marks the transition from summer to winter, in September ( Northern Hemisphere) or March ( Sout ...

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

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