The Dahme Flood Relief Canal, or Dahme-Umflutkanal in German

German language

German is a West Germanic language, related to and classified alongside English and Dutch. With an estimated 90 – 98 million native speakers, German is one of the world's major languages and is the most widely-spoken first language in the European Union....

, is a canal

Canal

Canals are man-made channels for water. There are two types of canal:#Waterways: navigable transportation canals used for carrying ships and boats shipping goods and conveying people, further subdivided into two kinds:...

 in the German

Germany

Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

 state of Brandenburg

Brandenburg

Brandenburg is one of the sixteen federal-states of Germany. It lies in the east of the country and is one of the new federal states that were re-created in 1990 upon the reunification of the former West Germany and East Germany. The capital is Potsdam...

. Its principal purpose is to divert water from the upper reaches of the River Spree

Spree

The Spree is a river that flows through the Saxony, Brandenburg and Berlin states of Germany, and in the Ústí nad Labem region of the Czech Republic...

 just below Leibsch

Leibsch

Leibsch is a locality in the municipality of Unterspreewald in the German state of Brandenburg. It is located on the River Spree in the Spreewald....

, to run into the River Dahme at Märkisch Buchholz

Märkisch Buchholz

Märkisch Buchholz is a small town in the Dahme-Spreewald district, in Brandenburg, Germany. It is situated on the Dahme River, 20 km northwest of Lübben and resp. 50 km southeast of Berlin.-Overview:...

.

The canal is entered from the River Spree by a lock

Lock (water transport)

A lock is a device for raising and lowering boats between stretches of water of different levels on river and canal waterways. The distinguishing feature of a lock is a fixed chamber in which the water level can be varied; whereas in a caisson lock, a boat lift, or on a canal inclined plane, it is...

 and is navigable downstream to Märkisch Buchholz. A weir

Weir

A weir is a small overflow dam used to alter the flow characteristics of a river or stream. In most cases weirs take the form of a barrier across the river that causes water to pool behind the structure , but allows water to flow over the top...

 here prevents direct access to the River Dahme, but a small inclined plane

Canal inclined plane

An inclined plane is a system used on some canals for raising boats between different water levels. Boats may be conveyed afloat, in caissons, or may be carried in cradles or slings. It can be considered as a specialised type of cable railway....

 allows canoe

Canoe

A canoe or Canadian canoe is a small narrow boat, typically human-powered, though it may also be powered by sails or small electric or gas motors. Canoes are usually pointed at both bow and stern and are normally open on top, but can be decked over A canoe (North American English) or Canadian...

s and small craft to by-pass the weir

Weir

A weir is a small overflow dam used to alter the flow characteristics of a river or stream. In most cases weirs take the form of a barrier across the river that causes water to pool behind the structure , but allows water to flow over the top...

 near Märkisch Buchholz.

The canal is 9.5 kilometres (5.9 mi) in length, and at about its mid-point crosses the Köthener See

Köthener See

Köthener See is a lake in Landkreis Dahme-Spreewald, Brandenburg, Germany. At an elevation of 43 m, its surface area is 1.48 km². It is located in the municipality of Märkisch Buchholz, Dahme-Spreewald district....

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