From the sluice of Geesthacht ( at kilometre 586 ) on downstream the Elbe is subject to the tides , the tidal Elbe section is called the Low Elbe ( Unterelbe ) . Soon the Elbe reaches Hamburg . Within the city-state the Unterelbe has a number of branch streams , such as Dove Elbe , Gose Elbe , Köhlbrand , Northern Elbe ( Norderelbe ) , Reiherstieg , Southern Elbe ( Süderelbe ) . Some of which have been disconnected for vessels from the main stream by dikes . In 1390 the Gose Elbe ( literally in ) was separated from the main stream by a dike connecting the two then-islands of Kirchwerder and Neuengamme . The Dove Elbe ( literally in ) was diked off in 1437/38 at Gammer Ort . These hydraulic engineering works were carried out to protect marshlands from inundation , and to improve the water supply of the Port of Hamburg . After the heavy inundation by the North Sea flood of 1962 the western section of the Southern Elbe was separated , becoming the Old Southern Elbe , while the waters of the eastern Southern Elbe now merge into the Köhlbrand , which is bridged by the Köhlbrandbrücke , the last bridge over the Elbe before the North Sea
North Sea flood of 1962
North Sea flood of 1962
Elbe