The Upper Harz Water Regale (German: Oberharzer Wasserregal) 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 (droit de régale) 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 (the preservation of a historic cultural landscape), 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. The water system covers an area of roughly 200 square kilometres (77 sq mi) within the Lower Saxon part of the Harz, the majority of structures being found in the vicinity of Clausthal-Zellerfeld, Hahnenklee, Sankt Andreasberg, Buntenbock, Wildemann, Lautenthal, Schulenberg, Altenau and Torfhaus.
The Water Regale
Regale in this context means a royal prerogative. Through the so-called Bergregal, or "mining rights", the monarch granted the right to mine and, through the Wasserregal, he granted the right to use local water supplies for the purpose of mining. Other water users, particularly mill owners, had a lower priority. This 'water regale' or 'right to use water' was part of the overall Bergfreiheit or mining rights that were valid in in Lower Saxony until the 1960s.
Mining and water
Mining becomes a very energy-intensive activity as soon as excavation extends any significant distance underground. In the Upper Harz, vein mining (Gangerzbergbau) was the main form of extraction, with excavation following the near-vertical lodes straight down into the earth. Only a few metres down the ingress of water increased the difficulty of excavation considerably.
Water Diversion and Storage Elements
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.
Due to the sheer number of structures and the length of the ditches the Upper Harz Water Regale is best explored on foot. Thanks to the Harzwasserwerke a large number of waterside footpaths have been created in recent years: the so-called Wasserwanderwege. Visitors can get to know about the typical elements that make up the Upper Harz Water Regale by means of information boards along the clearly marked routes. With a few exceptions, most of the ponds can be used by swimmers during the summer months. The majority are also are leased to local angling clubs.
Mining activity in the Harz goes back to the 10th and 11th centuries. The first water wheels in the Harz were erected in the 13th century in the Pandelbach valley southeast of Seesen. At that time mining, including this early used of the so-called waterworks (Wasserkünste) for the mines, was managed by the Cistercian abbey at Walkenried. The Black Death in the Middle Ages depopulated the Harz to a great extent and almost brought mining operations to a standstill. Another factor was probably that mining had reached its technical limits at the time with depths of up to about 60 metres.
A clear recovery followed from about 1520 onwards, initially at the instigation of the Duke of Brunswick-Wolfenbüttel, Henry the Younger. But it was his son, Julius, Duke of Brunswick-Lüneburg, who gave added impetus to existing mining operations in the Upper Harz and initiated the creation of a large number of ponds and ditches.
There are similar water supply systems in the historic silver mining region near Freiberg (Sachsen), in Norwegian Kongsberg, in Schemnitz (today part of Slovakia) and in Sweden, and records show that there was a regular exchange of experience and know-how between these regions. Nevertheless, the Upper Harz Water Regale, is the largest and most interconnected system of its kind in Europe, with significantly more dams and ditches as well as larger structures than all its counterparts elsewhere.