page_title: Upper Harz Water Regale
section_title: Water diversion and storage elements
hierarchical_section_title: Upper Harz Water Regale / Water diversion and storage elements
caption_attribution_description: Dammgraben bei Altenau, Bestandteil des Oberharzer Wasserregals
context_page_description: The Upper Harz Water Regale is a system of dams, reservoirs, ditches and other structures, much of which was built from the 16th to 19th centuries to divert and store the water that drove the water wheels of the mines in the Upper Harz region of Germany. The term regale, here, refers to the granting of royal privileges or rights in this case to permit the use of water for mining operations in the Harz mountains of Germany.
  The Upper Harz Water Regale is one of the largest and most important historic mining water management systems in the world. The facilities developed for the generation of water power have been placed under protection since 1978 as cultural monuments. The majority are still used, albeit nowadays their purpose is primarily to support rural conservation, nature conservation, tourism and swimming. From a water management perspective, several of the reservoirs still play a role in flood protection and the supply of drinking water. On 31 July 2010 the Regale was declared a UNESCO World Heritage Site affiliated with the Mines of Rammelsberg and the Historic Town of Goslar.
context_section_description: In all, 143 dammed ponds, 500 kilometres of ditch and 30 kilometres of tunnel were built for the collection, diversion and storage of the surface runoff water in the Upper Harz. In addition about 100 kilometres of drainage adits are included as part of the Regale.  These facilities were not, however, all in operation at the same time. The Harzwasserwerke today operates and maintains 65 dammed ponds, 70 kilometres of ditch and 20 kilometres of tunnel. Several smaller dammed ponds still belong to the Lower Saxon State Forestry Department or are even in private hands.
  The principle  of water diversion is to collect the water in ditches, running almost parallel to the contours of the slope, and to divert it to the mining areas. These supply channels can easily be ten or more kilometres long (like the Dam Ditch or the Upper Schalke Ditch). Sometimes the water so collected was not fed directly to the water wheels, but into large, artificial, dammed ponds (Teiche) which acted as reservoirs, in order to ensure enough water was available for the wheels even in times of drought. From the bottom outlets of these ponds the water could be led into a ditch system in order to power the water wheels. Usually several wheels were arranged one after another, like a cascade, so that the water could be used to drive more than one wheel. In order to lead the water over as many wheels as possible, it had to be collected, stored and routed around at the highest possible elevation.
  The technology of the time did not enable dams to be built with heights of more than about 15 metres. This meant that many small ponds had to be laid out rather than a few larger ones. By arranging the ponds in a cascade, water could be retained at a high elevation in order to drive as many water wheels as possible. A number of these pond cascades were built, comprising four to six ponds.
  The majority of water wheels were used to drive pumps. Occasionally, the power they generated had to be transmitted over several hundred metres to the mine itself using flat rods (Feldgestänge). Important mines also had a reciprocal water wheel which was used to provide power for transporting the ore and the material to be crushed. All water wheels were of the overshot type. Apart from a few reconstructions, the water wheels all disappeared during the last century.
caption: The Dam Ditch near Altenau
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