Eider Canal conservation areas. Eider Canal The Eider Canal (also called the Schleswig-Holstein Canal) was an artificial waterway in southern Denmark (later northern Germany) which connected the North Sea with the Baltic Sea by way of the rivers Eider and Levensau. Constructed between 1777 and 1784, the Eider Canal was built to create a path for ships entering and exiting the Baltic that was shorter and less storm-prone than navigating around the Jutland peninsula. In the 1880s the canal was replaced by the enlarged Kiel Canal, which includes some of the Eider Canal's watercourse. The canal's watercourse followed the border between the
Baltic Sea the Baltic. They include the major rivers of north Europe, such as the Oder, the Vistula, the Neman, the Daugava and the Neva. Additional fresh water comes from the difference of precipitation less evaporation, which is positive. An important source of salty water are infrequent inflows of North Sea water into the Baltic. Such inflows, important to the Baltic ecosystem because of the oxygen they transport into the Baltic deeps, used to happen regularly until the 1980s. In recent decades they have become less frequent. The latest four occurred in 1983, 1993, 2003 and 2014 suggesting a new inter-inflow period