A ''Kunstgraben'' is a type of man-made

water channel Water (chemical formula ) is an inorganic, transparent, tasteless, odorless, and nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living organisms (in which it acts as a ...

that was once used by mines to drive the water wheels needed for power, mine drainage and a host of other purposes. The term is German (plural: ''Kunstgräben''). Similar ditches supplying water mills in England are called leats.

Background

Until the invention of the

steam engine A steam engine is a heat engine that performs mechanical work using steam as its working fluid. The steam engine uses the force produced by steam pressure to push a piston back and forth inside a cylinder. This pushing force can be trans ...

, water power was the main source of energy utilised by the various mechanical engines employed in the mining industry, such as water wheels, reversible water wheels,

water-column engine The water engine is a positive-displacement engine, often closely resembling a steam engine with similar pistons and valves, that is driven by water pressure. The supply of water was derived from a natural head of water, the water mains, or a s ...

s or water turbines. To enable mine workings to be driven ever deeper, more and more power was needed. The water available in the vicinity of the pits was insufficient for that purpose and springs frequently dried up as a result of be diverted for use in the mines. As a result, the water needed for the mine workings sometimes had to be transported over long distances.

Usage

The aim was to have the greatest possible height difference at the site of the water power engine. This difference is known as the height of impact (''Aufschlaghöhe''). To achieve this the ''Kunstgräben'' were laid with only a very slight gradient, so that they resembled contours in the terrain and followed all the twists and turns of the valleys. In order to overcome natural obstacles ''Kunstgräben'' were frequently led along the bottom of tunnels in so-called ''Röschen'' or, more rarely, over aqueducts; the best-known ''Kunstgraben'' aqueducts being the Altväter Bridge near

Halsbrücke Halsbrücke is a municipality and village in the district of Mittelsachsen, in Saxony, Germany. It is situated just north of Freiberg, on the banks of the Freiberger Mulde river. Geography Halsbrücke lies 5 km north of Freiberg on the le ...

and the Sperberhai Dyke in the Harz Mountains. Typically a ''Kunstgraben'' started at a weir or divert (''Wasserteiler'') and ran along ''Röschen'' and via water storage ponds or '' Kunstteiche'' to the pit. The water power engine usually had a headrace and a tailrace (''Aufschlagrösche'' and ''Abzugsrösche''). A footpath was laid parallel to the ''Kunstgraben'' that acted as an access route for the ditch overseer (''Grabensteiger''), whenever he went to the weir to adjust the paddles. These paths are frequently used as walking trails today, where they have survived. The ''Kunstgräben'' were often covered by rough boards (''Schwarten''). These acted, on the one hand, to keep the ditches clear and protect them from becoming overgrown and, on the other hand, to protect the ditches from destruction by cattle. It also helped to defend the owners of the ditches from the claims of neighbouring landowners, who had otherwise to be compensated for the loss of income and land resulting from the construction of ''Kunstgräben'' and who often brought claims as a result of allegedly drowned livestock and game.

Well-known examples

* Dyke Ditch (''Dammgraben'') * Neugrabenflöße * Upper Harz Ditches * Upper Harz Water Tunnels

Sources

* * * * Herbert Pforr: ''Das erzgebirgische Kunstgrabensystem und die Wasserkraftmaschinen für Wasserhaltung und Schachtförderung im historischen Freiberger Silberbergbau''. In: Bergbau Heft 11/2007, S. 502-505
Digitalisat
* * {{citation , surname1=Otfried Wagenbreth , editor-surname1=Eberhard Wächtler , title=Der Freiberger Bergbau: Technische Denkmale und Geschichte , edition=2nd , publisher=Deutscher Verlag für Grundstoffindustrie , publication-place=Leipzig , isbn=3-342-00117-8 , date= 1988 , language=German

External links

Historic diagrams of water systems used in mining at mineralienatlas.de