Diepentaler Talsperre, reservoir

The Diepentaler Talsperre is a reservoir near Leichlingen in North Rhine-Westphalia, formed behind a dam built in the early 20th century. The water body is surrounded by forested slopes and features walking and cycling paths along with areas for water-based recreation.

The dam was built between 1902 and 1908 by August Halbach, solely to generate electricity, not for water supply. The reservoir flooded the seat of the Knights of Diepental, whose descendants, the Katterbach family, were made known through a novella by Levin Schücking and Annette von Droste-Hülshoff. After heavy rain in January 2011 the dam could no longer hold the water, and the Cologne district government ordered the water level lowered. In July 2016 the Wupperverband announced plans to dismantle the dam and restore the Murbach stream.

The reservoir takes its name from Diepental, the valley whose seat of the Knights of Diepental was flooded when the dam was built. Their descendants, the Katterbach family, became known through Levin Schücking and Annette von Droste-Hülshoff's novella Das Stiftsfräulein. Today the grounds remain private property of the Halbach family but are open to the public, with a guesthouse, holiday cottages, minigolf and angling around the water.

The site and the reservoir are privately owned by the Halbach family but open to the public. The main dam is an earth embankment about 10 m high with a 100 m long crest; a road dam separates the forebay from the main reservoir. In July 2016 the Wupperverband announced plans to dismantle the dam and restore the Murbach stream, so conditions may change.

The reservoir flooded the seat of the Knights of Diepental; their descendants, the Katterbach family, became known through Levin Schücking and Annette von Droste-Hülshoff's novella Das Stiftsfräulein (also titled Eine dunkle Tat). The dam and grounds remain private property of the Halbach family but are open to the public.