The Innerste Dam (german: Innerstetalsperre) is a

dam A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use ...

on the

Innerste The Innerste is a river in Lower Saxony, Germany. It is a right tributary of the Leine river and in length. Origin of the name The river name is not related to the German word ''innerste'' meaning innermost. ''Innerste'', in earlier times c ...

river, which lies near

Langelsheim Langelsheim is a town in the district of Goslar in Lower Saxony, Germany. Geography The municipality is situated between the river Innerste and its tributary Grane, on the northern edge of the Harz mountain range and the Harz National Park, loc ...

and Wolfshagen in the

Harz mountains The Harz () is a highland area in northern Germany. It has the highest elevations for that region, and its rugged terrain extends across parts of Lower Saxony, Saxony-Anhalt, and Thuringia. The name ''Harz'' derives from the Middle High German ...

. It was built between 1963 and 1966 and belongs to the ''

Harzwasserwerke The Harzwasserwerke GmbH (; English: Harz Water Works Limited) is a major German water company and dam operator based in Hildesheim, located within the German federal state of Lower Saxony. Founded in 1928, the Harzwasserwerke were tasked with sup ...

''. Its purposes are the supply of

drinking water Drinking water is water that is used in drink or food preparation; potable water is water that is safe to be used as drinking water. The amount of drinking water required to maintain good health varies, and depends on physical activity level, a ...

flood protection 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 ...

, water flow regulation and

hydroelectric power Hydroelectricity, or hydroelectric power, is electricity generated from hydropower (water power). Hydropower supplies one sixth of the world's electricity, almost 4500 TWh in 2020, which is more than all other renewable sources combined and ...

generation. The average annual discharge through the Innerste Dam is 60 million m³.

Structures

The Innerste is an

earth-fill 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 ...

with multiple, external, asphaltic concrete layers. It has an inspection gangway along its whole length on the upstream apron. In front of the upstream base of the dam is a shaft spillway (a flood overflow tower), into which also the bottom outlet is integrated. The water of the Innerste Dam can be pumped via a 4.6 km long diversion channel to the

Grane Dam The Grane Dam (german: Granetalsperre) is a dam above the village of Astfeld/Herzog-Juliushütte in the borough of Langelsheim in the Lower Saxon part of the Harz mountains. Dam system It is the newest dam in the Harz, built in 1969 in the ...

further east, where it can be used for

water treatment Water treatment is any process that improves the Water quality, quality of water to make it appropriate for a specific end-use. The end use may be drinking water, drinking, industrial water supply, irrigation, river flow maintenance, water recrea ...

. From 2003 to 2005 the reservoir was completely emptied and renovated, especially the asphalt sealing and the bottom outlet. This work was finished in September 2005.

Flood control

Because the reservoir only has a limited flood control capacity (i.e. its capacity is relatively small in relation to the annual discharge), it can only check flooding within certain limits. The flood relief facility (

spillway A spillway is a structure used to provide the controlled release of water downstream from a dam or levee, typically into the riverbed of the dammed river itself. In the United Kingdom, they may be known as overflow channels. Spillways ensure tha ...

) is used about every two years. Nevertheless, even when the Innerste Dam overflows, the level of retention significantly reduces and delays flooding.

Recreation

The

reservoir A reservoir (; from French ''réservoir'' ) is an enlarged lake behind a dam. Such a dam may be either artificial, built to store fresh water or it may be a natural formation. Reservoirs can be created in a number of ways, including contro ...

may be used by sailing and rowing boats and for angling and camping. The

Innerste Valley Railway The Innerste is a river in Lower Saxony, Germany. It is a right tributary of the Leine river and in length. Origin of the name The river name is not related to the German word ''innerste'' meaning innermost. ''Innerste'', in earlier times c ...

is an old railway line, that had a halt by the Innerste Dam.

Gallery

File:Innerstetalsperre_UEberlauf.jpg, Shaft spillway in the reservoir File:Ueberlaufturm-18.10.03.jpg, Shaft spillway during renovation work File:Innerstestausee_Niedrigwasser.jpg, Reservoir at low level File:Innerste_im_Stausee.jpg, Innerste at low water File:Innerstetalsperre Panorama.jpg, View of the Innerste Dam

Sources

External links