Jade Estuary

The Jade Bight (or Jade Bay;German: Jadebusen) is a bight or bay on the North Sea coast of Germany. It was formerly known simply as Jade or Jahde. Because of the very low input of freshwater, it is classified as a bay rather than an estuary.

About 180 km² (70 mi²) in area, the Jade was largely created by storm floods during the 13th and 16th centuries. Since the early 14th century, it has joined eastward to the estuary of the river Weser. For some time, there were three permanent connecting branches and one flood bed between the river and the bight, forming an estuarine delta. The first of these junctions was closed in 1450 by dikes and the last one in 1515. However, about a century passed before most of the area flooded by these connections was regained for pasture and arable land.

In the west, the Jade extended far into the Frisian peninsula. From the early 16th century, a number of dikes were built against the storm floods and to gain arable land. The main dike, Ellenser Damm, was built between 1596 and 1615 by the County of Oldenburg before the agreement with the objecting County of East Frisia was finished successfully.

The extension of Jade Bight and its branches fragmented the free Frisian territory of Rüstringen in Bant in the northwest, most of which has disappeared in the waves, Bovenjadingen ("Above the Jade") with the low moraine hills of Friesische Wehde in the southwest, Butjadingen ("Outside the Jade") in the northeast, which was an island for almost two centuries, and Stadland ("Bank-Land"), which became a narrow island along the left bank of the Weser in 1384. The devastation by floods and the losses of land weakened the Frisian community. In the years about 1400, the Free City of Bremen tried to rule Standland and Butjadingen. In the beginning of 16th Century, all countries around Jade Bight were conquered by the Counts of Oldenburg.

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