Upper Harz Water Tunnels


The Upper Harz Water Tunnels are part of the Upper Harz Water Regale - a network of reservoirs, ditches, tunnels and other structures in the Harz mountains of central Germany. The German term Wasserlauf refers to the underground element of the network of watercourses used in the historic silver mining industry of the Upper Harz. This network of ditches and tunnels was used to supply the mines with headrace waters for their water wheels from the 16th century onwards. In the system of the Upper Harz Water Regale there are over 35 such tunnels with a total length of about 30 km.

Construction

Although explosives were already in use in the 17th century in the mines of the Upper Harz, tunnels continued to be hewn out by hand, that is with hammer and chisel for much longer. The reason was that there were difficulties in determining the right amount of gunpowder and fears that tunnels running just under the surface would collapse or that the explosive would produce fissures in the rock causing water to leak away. Almost all water tunnels were driven by counter-heading. Until the 18th century the miners excavated tunnels by following the weakest rock; this sometimes created a zigzag route that deviated significantly from the direct line. Not until the 19th century were tunnels driven in a strictly direct line using explosives.
The incline necessary to create a flow of water often amounted to less than 1 ‰. The profile of the older tunnels, that had been driven with hammer and chisel, was sometimes as small as 1.20 m high and 0.80 m wide. The newer tunnels, however, were generally 2 m high and 1 m wide.
Compared with ditches, tunnels had the important advantage that the water flowing through them underground could not freeze up. The tunnels were laid primarily to short cut the long ditch runs around mountains. Such cuts also produced a steeper incline. This raised the flow velocity and hence the hydraulic capacity of the watercourse. The disadvantage of tunnels was the high investment cost of building them.

List of working Upper Harz water tunnels

The working tunnels shown in this table follow the order in the latest listing by Preussag, which is based on their use in the various power stations.
English NameGerman NameBuiltLengthRoute
Kellwasser Tunnel IKellwasser Wasserlauf I1821170 mDyke Ditch to the Nabe valley
Kellwasser Tunnel IIKellwasser Wasserlauf II1821229 mBlochschleife to Wiege on the Dyke Ditch
Rothenberg TunnelRothenberger Wasserlauf1868775 mDyke Ditch: crosses the Rothenberg
Coventhai TunnelCoventhaier Wasserlauf1852540 mDyke Ditch: crosses the Coventhai
Dietrichsberg TunnelDietrichsberger Wasserlauf18631044 mDyke Ditch from Fortune Pond to the "Fenster"
Bielenwiese TunnelBielenwieser Wasserlauf1864357 mDyke Ditch from "Fenster" to "Teilung"
Mönchstal TunnelMönchstaler Wasserlauf1677474 mDyke Ditch from Mönchstal into the Upper Hausherzberg Pond
Franz August TunnelFranz Auguster Wasserlauf1832632 mDyke Ditch from the Teilung into the Lower Peacock Pond
Jägersbleek TunnelJägersbleeker Wasserlauf1771132 mTräncke Ditch to the Jägersbleek Pond
Huttal TunnelHuttaler Wasserlauf1763783 mHirschler Pond to the Huttaler Widerwaage
Fortune TunnelFortuner Wasserlauf1785777 mJägersbleek Ditch into the Middle Peacock Pond
Prince Wallis TunnelPrinz-Walliser Wasserlaufum 1740563 mNassenwiese Ditch into the Johann Friedrich Tunnel
Johann Friedrich TunnelJohann-Friedricher Wasserlauf1673805 mFrom the Johann Friedrich Pond to the Dorothea Water Wheel Ditch
Kellerhals TunnelKellerhalser Wasserlauf1842501 mFrom the Middle Kellerhals Pond to the New Kellerhals Ditch, later used in the course of the Zellerfeld Ditch
Winterwiese TunnelWinterwieser Wasserlaufvor 1690488 mFrom the Zellerfeld Ditch into the Jungfrau Ditch / Middle Zechen Pond
Bremerhöhe TunnelBremerhöher Wasserlauf1704732 mBremerhöhe Ditch to the Rosenhof Mining Area
Bärenbruch TunnelBärenbrucher Wasserlauf1949940 mFrom the Bärenbruch Pond into the "Upper Rosenhof Chute"
Upper Schwarzenbach TunnelOberer Schwarzenbacher Wasserlauf1808760 m"Upper Rosenhof Chute" to the Hasenbacher Widerwaage
Upper Hasenbach TunnelOberer Hasenbacher Wasserlauf1811638 m"Upper Rosenhof Chute" to Hasenbacher Widerwaage
Upper Flambach TunnelOberer Flambacher Wasserlauf1763780 m"Upper Rosenhof Chute" from Flambach to the Johannis valley
Upper Johannistal TunnelOberer Johannistaler Wasserlauf18391014 m"Upper Rosenhof Chute" Johannistal to the Klein Clausthal
Upper Klein Clausthal TunnelOberer Klein-Clausthaler Wasserlauf1776492 m"Upper Rosenhof Chute" from Klein Clausthal to the Rosenhof Mines
Ziegenberg TunnelZiegenberger Wasserlauf1847413 m"Lower Rosenhof Chute" from Ziegenberg Pond to the Schwarzenbach
Lower Schwarzenbach TunnelUnterer Schwarzenbacher Wasserlauf1870524 m"Lower Rosenhof Chute" from the Schwarzenbach to the Hasenbach
Lower Hasenbach TunnelUnterer Hasenbacher Wasserlauf1845959 m"Lower Rosenhof Chute" from the Hasenbach to the Flambach
Lower Flambach TunnelUnterer Flambacher Wasserlauf1844973 m"Lower Rosenhof Chute" from the Flambach to the Johannistal
Lower Johannistal Tunnel IUnterer Johannistaler Wasserlauf I1835558 m"Lower Rosenhof Chute" from the Johannistal to the Klein Clausthal
Lower Johannistal Tunnel IIUnterer Johannistaler Wasserlauf II1835234 m"Lower Rosenhof Chute"
Lower Klein Clausthal TunnelUnterer Klein-Clausthaler Wasserlauf1792791 m"Lower Rosenhof Chute" from the Kl. Clausthal to the Rosenhof Mines
Dorothea RöscheDorotheer Röschevor 1771325 mDrainage for the water wheel at Dorothea Pit
Gesehe TunnelGeseher Wasserlauf1698722 mRehberg Ditch to the Gesehr / St. Andreasberg
Schulte AditSchulte Stollen18381220 mFrom the Innerste river to the Wiemannsbucht
Upper Eichelberg TunnelOberer Eichelberger Wasserlauf18891110 mFrom Wiemannsbucht to Schönhofsblick
Lower Eichelberg TunnelUnterer Eichelberger Wasserlauf1855230 mDrain from the Knesebeck Shaft

List of disused Upper Harz water tunnels

"Disused" refers to all those tunnels that are no longer in service. Some of these are completely preserved; others, however, have largely fallen into ruin. The following list makes no claim to being complete.
English NameGerman NameBuiltLengthRoute
Old Dietrichsberg TunnelAlter Dietrichsberger Wasserlauf1662260 mDyke Ditch: Bypasses the Dietrichsberg; became superfluous on the construction of the New Dietrichsberg Tunnel in 1863.
Old Upper Klein Clausthal TunnelAlter Oberer Klein-Clausthaler Wasserlauf120 mUpper Rosenhof Chute: Bypasses the Hüttenkopf
Old Lower Klein Clausthal TunnelAlter Unterer Klein-Clausthaler Wasserlauf200 mLower Rosenhof Chute: Bypasses the Hüttenkopf
Benedict TunnelBenedikter Wasserlauf100 mUpper Kehrzug Ditch into the Hirschler Pond
Kalte Küche TunnelKalte Küche Wasserlauf1821410 mDyke Ditch: crosses the Rothenberg; tunnel closed on the construction of the Rothenberg Tunnel in 1868.
Crane TunnelKranicher Wasserlauf1878600 mfrom the bottom outlet of the Crane Pond to the Lower Raft Pond
Langer TunnelLanger Wasserlaufbefore 1815150 mShort channel from the Oker region to the Langer Pond
Nassenwiese TunnelNassenwieser Wasserlauf250 mfrom the Nassenwiese Ditch to the Johann Friedrich Tunnel
Piss Valley TunnelPisstaler Wasserlauf17321100 mStadtweg Ditch to Bockswiese
Polsterberg TunnelPolsterberger Wasserlauf17671,23 kmOriginally a gallery in the Eisenstein mine; between 1767 and 1813 tunnel from the Polsterberg Pumpworks to the Huttal Pond
Schwarzenberg TunnelSchwarzenberger Wasserlauf1813730 mLinks the outlet area of the Söse with the Oker river
Tannhai TunnelTannhaier Wasserlauf1875430 mLinks the Kellerhals Pond, Kellerhals Tunnel to Bockswiese, Wäsche Ditch