Lehnitzsee, Oranienburg

Lehnitzsee is a narrow toteis lake in the Zehdenick-Spandau Havel lowlands in northern Brandenburg. It takes its name from the village of Lehnitz on the southern shore of the lake. Lehnitz and the Lehnitzsee today belong to the urban area of Oranienburg. The lake stretches for 2.4 kilometers in a north-south direction, with a width between 250 and 470 meters. Originally, the Lehnitzsee was fed by the Stintgraben and drained into the Havel via the Lehnitzfließ.

In 1914, the lake became part of the Havel-Oder waterway. Here, a navigable connection was created from the Malz Canal via the Lehnitz Lock to the northern shore of the lake. The old outflow called Lehnitzfließ of the Lehnitzsee gave way to a canal connection to the Oranienburger Havel. The construction measures were associated with a significant lowering of the water level, which reduced the area of the lake. Its catchment area, on the other hand, increased enormously.

Industrial and port facilities on the western shore of the lake have largely disappeared.

In addition to commercial shipping, which today only crosses the lake, which is part of a federal waterway, it is mainly important for sports and excursion shipping and its shore areas as a local recreation area.

Lake Lehnitz is a calcareous, unstratified lake with a relatively large catchment area. Assessed as potentially mesotrophic, the lake was weakly eutrophic in 2014 with an LAWA trophic index of 3.0. Both the ecological and chemical status of Lake Lehnitz are assessed as 3 on a five-point scale according to the EC Water Framework Directive.

In Sarah Kuttner's novel Kurt, the first-person narrator takes a swimming trip to Lake Lehnitz with her partner Kurt.