[1] The islands of Dradenau were sold to Hamburg in 1445 by Count Otto von Holstein.

[3] As part of the Hamburg port extensions, the Köhlfleet, another channel north of Dradenau channel, was reclaimed, which connected the islands to Waltershof, an area of Hamburg.

By the late 19th century, the channel disappeared entirely due to silting and the construction of the port of Hamburg.

[3] A sewage treatment plant, Klärwerk Dradenau, currently exists where it used to flow.

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