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

water channel Water is an inorganic compound with the chemical formula . It is a transparent, tasteless, odorless, and nearly colorless chemical substance. It is the main constituent of Earth's hydrosphere and the fluids of all known living organisms ( ...

that was once used by mines to drive the

water wheel A water wheel is a machine for converting the kinetic energy of flowing or falling water into useful forms of power, often in a watermill. A water wheel consists of a large wheel (usually constructed from wood or metal), with numerous b ...

s needed for power, mine drainage and a host of other purposes. The term is German (plural: ''Kunstgräben''). Similar ditches supplying

water mill A watermill or water mill is a mill that uses hydropower. It is a structure that uses a water wheel or water turbine to drive a mechanical process such as milling (grinding), rolling, or hammering. Such processes are needed in the production ...

s in England are called

leat A leat (; also lete or leet, or millstream) is the name, common in the south and west of England and in Wales, for an artificial watercourse or aqueduct dug into the ground, especially one supplying water to a watermill or its mill pond. Othe ...

Background

Until the invention of the

steam engine A steam engine is a heat engine that performs Work (physics), 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 (locomotive), cyl ...

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

water wheels A water wheel is a machine for converting the kinetic energy of flowing or falling water into useful forms of power, often in a watermill. A water wheel consists of a large wheel (usually constructed from wood or metal), with numerous blade ...

, reversible water wheels, water-column engines or

water turbine A water turbine is a rotary machine that converts kinetic energy and potential energy of water into mechanical work. Water turbines were developed in the 19th century and were widely used for industrial power prior to electrical grids. Now, t ...

s. 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 lef ...

and the Sperberhai Dyke in the

Harz Mountains The Harz (), also called the Harz Mountains, is a Mittelgebirge, 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 nam ...

. Typically a ''Kunstgraben'' started at a

weir A weir or low-head dam is a barrier across the width of a river that alters the flow characteristics of water and usually results in a change in the height of the water level. Weirs are also used to control the flow of water for outlets of l ...

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 The Dyke Ditch () is the longest artificial ditch in the Upper Harz in central Germany. Its purpose was to collect surface runoff for the operation of the Upper Harz mining industry from precipitation-heavy regions a long way away (particularly ...

(''Dammgraben'') *

Neugrabenflöße The Neugrabenflöße (also called the ''Floßgraben''), was a roughly 18 km long '' Kunstgraben'' dating to the 17th century. It enabled the rafting of timber for the mining and smelting industries in the Ore Mountains of eastern Germany. It r ...

Upper Harz Ditches The Upper Harz Ditches (, ) are hillside Kunstgraben, ditches, running roughly parallel to the contour lines, that were laid out in the Upper Harz in Germany from the 16th to the 19th centuries to supply water power to the silver mines there. The ...

Upper Harz Water Tunnels The Upper Harz Water Tunnels (, ) are part of the Upper Harz Water Regale - a network of Kunstteich, reservoirs, Kunstgraben, ditches, tunnels and other structures in the Harz mountains of central Germany (geography), central Germany. The German ...

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