The Sperberhai Dyke is in fact an aqueduct

Aqueduct

An aqueduct is a water supply or navigable channel constructed to convey water. In modern engineering, the term is used for any system of pipes, ditches, canals, tunnels, and other structures used for this purpose....

 which forms part of the Upper Harz Water Regale

Upper Harz Water Regale

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...

 network of reservoirs, ditches, dams and tunnels in the Harz mountains of central Germany

Central Germany (geography)

In geography, central Germany describes the areas surrounding the central point of modern-day Germany.The town of Niederdorla, in the state of Thuringia, claims to be the most central town in Germany...

. It carries the water of the Dyke Ditch

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 . It was laid in 1732 and continually extended eastwards until 1827...

 over the depression of the Sperberhai to the Clausthal

Clausthal-Zellerfeld

Clausthal-Zellerfeld is a town in Lower Saxony, Germany. It is located in the southwestern part of the Harz mountains. Its population is approximately 15,000, Clausthal-Zellerfeld is also the seat of the Samtgemeinde Oberharz....

plateau.

The Sperberhai Dyke was built in 1732 - 34 in order to satisfy the rising demand for water power for the water wheels of the Clausthal mines. The water crossed the embankment in a channel along its crest. The channel is only visible today at its western end. Its hydraulic capacity at peak times was up to 1,000 litres per second.

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