Anthropogenic influence on riverine ecosystems has caused a drastic decline of natural floodplain ecosystems. Estuarine floodplains with their tidal influence are highly dynamic and harbour many rare and threatened plant species in Central Europe. This study focuses on the Dove Elbe River, which is an anabranch of the Elbe Estuary in Northwest Germany. In 1951, a sluice was built to disconnect the Dove Elbe River from the tidal influence of the Elbe River. This study aims to analyse changes in vegetation and environmental variables from 1951 to 2016. Therefore, 98 plots with vegetation records from 1951 along the Dove Elbe River were reassessed in 2016. 45 of the original plots were inventoried again, as 53 of the original plots were under water or majorly transformed, e.g. used as arable fields. Changes in vegetation type, diversity measures, species composition, and Ellenberg Indicator Values (EIV) for moisture and nutrition were analysed. The most remarkable outcome was the almost complete loss of wet pioneer vegetation types. While willows and other woody species were established on several plots with the former reed, Angelica archangelica community or Phalaris arundinacea community vegetation type, the intensification of agricultural land use caused a strong decline in species richness on grasslands. Overall, species richness per plot also decreased, and some threatened species were lost. The weighted average EIV for moisture clearly declined on all plots, which indicates drier conditions today compared to the mid-20th century. Our results reinforce the argument to restore the tidal influence along the Dove Elbe River.