Hohendeicher Lake

The Hohendeicher Lake, or Oortkatensee, is an artificially created bathing lake in the southeastern part of Hamburg, located in the districts of Ochsenwerder and Kirchwerder in the marshlands. The lake lies in the area of the former foreland of the two old Elbe dikes, Ochsenwerder Elbdeich and Warwischer Hinterdeich. The Hohendeicher Lake, along with its catchment area, was designated as a nature reserve in 1977.
During the storm tide of 1962, the Ochsenwerder Elbdeich and the Warwischer Hinterdeich were at high risk, but flooding did not occur. Consequently, the "relevant storm tide water level" was estimated at NN +6.70 meters, which is 1.10 meters higher. An increase in the height of the old dikes was not possible as they were built upon. The new Overwerder main dike was constructed on the Elbe side of the old foreland, which also shortened the dike line. The materials gravel and clay for the construction of this dike were extracted from the area between the old and new dikes. In the northern area, a new inland and sports boat harbor, Oortkaten, was established on the Elbe side.

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