17 January 2014

The second inhabited island on the Danube

is situated in the town of Neuburg an der Donau, Germany. „Second” means space and not time in this case. It would be quite difficult to trace back the first inhabited island On the Danube in time. It is concievable that island had been washed away since then. In terms of space we have an easier task, because if we do not count the more or less artificial island of Regensburg, the Leopoldineninsel is the only inhabited island with the Neu-Ulmer Island on the entire German Danube section.

This fame goes not always with the reputation. If it would be so, there would be much more information on this island. The Leopold Island can be found at the 2477th river kilometer out of the rivers total length: 2840 km. The river is still fairly narrow here, we are barely 400 kilometers from the source, halfway between the mouth of Lech and Ingolstadt. This section is mostly covered by rivereine forests, there is only one point where the higher ground meets the river; this permanent crossing is where Neuburg an der Donau was founded. We are looking eastwards on these two postcards, down on the Danube valley. In the middle you find the ducal English landscape gardens, a former riverine forest. Before the river regulation works forests like this embraced the river on both sides all the way down to Ingolstadt. This continuous floodplain was interrupted by the neuburgian Elisen bridge.

Neuburg an der Donau - despite its name (Newcastle) is a rather old town, between 778 and 809 it became the bishop’s seat of Augsburg and later (between 1505-1779) the capital of the Pfalz-Neuburger Duchy. The two postcards represent the view from the Duke’s residence on a hill (the black and white postcard has more details). All maps and engravings illustrate the important Elisen bridge. But the Leopoldinen Island is missing from the maps. Why?

Copper engraving by Matthaeus Merian: Topographia Germaniae, 1644 /wikipedia.org/
Generalization is an option which causes the difference between the city view and the map below (engraved almost in the same time as the below map). During generalization the maker of the map can decide which are the most important objects to visualize on his map. And he also decides if the object's dimensions are worthy to draw them. It is possible the small Leopoldineninsel fell prey to generalization, as well it is is missing from all other maps from this era. Although we notice two more islands on the Danube just downstream Neuburg an der Donau, they do not exist anymore as islands. But their shape and landcover still resembles us the riverine forest it once was. It became the english landscape garden of the Pfalz-Neuburger duke.

Map of Neuburg, between 1716-1730 /oldmapsonline.com/
The Leoplodinen Island takes the shape of a prolated drop, on its downstream tip a growing sandbank indicates a constant expansion of land.

Flooded by the Danube, 1999 /forrás/
Since there was no other flood-prevention works on the island than the pavement works in 1903 the high water often indundates the Leopoldineninsel. The picture on the left shows the situation at the Pentecost flood in 1999. Right after this flood, between 2003-2005 flood prevention works begun on the island.  It has costed a stiff prize of 3 million euros. They fixed the pavement on the riverside, ruined by ice and floods, built a mobile and permanent flood-protection wall. A new rainwater-pump was installed, and the doors and windows of the island houses received a  seperate defence system. If a flood comes, the inhabitants don't have to worry, they just put steel barriers in the existing profiles, so the Danube won't pour through into their living room. The rainwater-pump prevents the rainfall from accumulating in the bowl-shaped island between the anti-flood walls. It starts to work automatically when the water can not run off to the river by gravity.
The Leopoldinen Island and the Old Town from a bird's eye view /photo: K. Leidorf/

In Germany there is much less discharge on the Danube than in the lower countries, the river regulation works casued almost all Danubian islands to disappear. There is no room for them anymore in the channelized river bed. As a survivor, the Leopoldineninsel in Neuburg an der Donau is a real pecularity!

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