Zehdenick Lock

The Zehdenick lock is located at kilometre 15.90 of the Upper Havel Waterway in the town of Zehdenick in the district of Oberhavel in northern Brandenburg.
The first lock in the former Mühlenstau in the town of Zehdenick was built around 1742, presumably as a boiler lock. The origin of today's lock system dates back to 1813. The inland boatmen and raftsmen used the Havel, also known as the Schnelle Havel, which flows in many turns with strongly varying width and sometimes insufficient depth, between Zehdenick and Liebenwalde. Year after year, several thousand barges and rafts passed through this river despite the poor conditions. To improve shipping conditions, a side canal was built east of the Havel. It branches off from the old part of the Voßkanal at Bischofswerder and reaches the Havel again below Zehdenick.
Other necessary structures were the Krewelin lock and the Bischofswerder lock as well as the Zehdenick building yard arch. It serves to divert the water level peaks of the Havel into the Schnelle Havel. The Freiarche near Höpen is used to drain the flood water of the Döllnfließ, which comes from the Schorfheide. These facilities, including the approximately 14-kilometre-long canal, were completed within two and a half years from spring 1880 to autumn 1882. The name Voßkanal, previously only used for a small canal between the Finow Canal near Liebenwalde and the Schnelle Havel near Bischofswerder, was now transferred to the entire new canal. During the construction period of the Voß Canal between Zehdenick and Liebenwalde, the lock in Zehdenick was renewed at the same time. Since the lock was no longer able to cope with shipping traffic, it was converted into a so-called double-chamber lock from 1907 to 1909. Until 1911/12, both lock chambers were operated in parallel. The old lock chamber was finally shut down around 1930.
The lock chamber is 44.90 metres long and 9.60 metres wide. The usable length is 43.40 metres, including a safety distance of 0.75 metres from the lock gates. The water depth in the lock at Unterwasser is 1.95 metres on average.

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