Once, this seemingly peaceful lake played a vital role. This is the Alte Süderelbe. It was once the main shipping route to Hamburg’s port. Vessels used this path to reach Harburg’s harbor until the 20th century. The storm flood of 1962 changed everything. Finkenwerder became connected to the mainland.
After the devastating storm flood in 1962, the Alte Süderelbe was cut off from the Elbe. It transformed from a tidal river into a still body of water. Though tides no longer influence it, its shallow waters became a haven. Rare species of animals, plants, and amphibians found refuge here.
Imagine this area before 1790. The Süderelbe flowed powerfully. It branched off from the Köhlbrand. It emptied into the Unterelbe. Around 1790, most of the Süderelbe’s water was diverted into the Köhlbrand. The remaining section became known as the Alte Süderelbe.
In 1963, the connection to the Elbe was closed. This happened near the Mühlenberger Loch. It was raised and sealed off with dikes. The Alte Süderelbe no longer experienced tidal influence. A road now crosses the northwestern barrier. It leads to Neuenfelde and Cranz. The Airbus factory’s runway also sits atop it.
The Alte Süderelbe isn’t just a body of water. It acts as a “Vorfluter.” It drains a vast area of about 90 square kilometers. This includes Finkenwerder and Altes Land extending to Harburg. Without it, the area would be prone to flooding. The Alte Süderelbe is essential for irrigating the region’s many fruit orchards. A sophisticated ditch system ensures consistent irrigation of the plantations.
The Alte Süderelbe stretches about 5700 meters. Its maximum width reaches 150 meters. The water’s depth is shallow. It averages between 1.5 to 2.0 meters. Some western parts reach depths of 3.5 meters. Its total area spans 60 hectares. This makes it Hamburg’s third-largest lake, after the Alster and Hohendeicher See.
Today, a portion of the Alte Süderelbe is a designated nature reserve. This protects the Finkenwerder Süderelbe’s unique ecosystem. Fish thrive in its waters. Anglers can find carp, bream, zander, and eels. These species benefit from the rich nutrients in the muddy waters. However, fishing is strictly prohibited in the nature reserve zones.
The Alte Süderelbe faced another challenge during the expansion of Finkenwerder harbor. Landfills reduced its size. This was especially in the area east of the Hamburger Aluminiumwerke. It shrunk to the size of a drainage ditch.
At the southeastern end, near Auedeich, a connection remains. The Deichsiel Storchennest links it to the Finkenwerder Vorhafen. The Schleusenfleet also provides inflow. It comes from the Moorwettern and Moorburger Landscheide.
The Alte Süderelbe has a rich history. Its future involves balancing nature, agriculture, and recreation. It remains a vital part of Hamburg’s landscape. Its story reminds us of the ever-changing relationship between humans and nature.