The
new landscape at the mouth of the Ybbs
The
river mouth today displays a keen diversity of habitat structures,
and the Ybbs river branches into a number of distributaries
separated by islands. The new delta at the mouth now encompasses
an enlarged area of about 9 hectares in total.
FOTOS
of the
Redevelopment
The
Ybbs is one of the largest rivers in Lower Austria. Its mouth lies
near the city of Ybbs an der Donau. The river and the Danube form
part of the Natura 2000 “Lower Austrian Alpine Foothills
Rivers” region, which also includes the Pielach, Melk and Erlauf
rivers. The previously natural River Ybbs has been reworked in
four stages since 1891. Adaptation of the mouth of the Ybbs took
place in 1971. We know today that adapting rivers entails a number
of problems. From an ecological point of view, it led to a massive
reduction in the available habitat for many species of animals.
The work was also partly responsible for the decline in previously
abundant fish stocks. In 1940 the mouth still consisted of islands,
gravel banks and branches.
|
Aerial
picture of the mouth of the Ybbs in 1940 |
The
objective was to create characteristic fluvial habitats in the
zone where the Ybbs flows into the Danube. Prior to the LIFE
project, flow regulation at the river mouth had resulted in a
dearth of gravel banks, gravel islands and natural shore zones.
|
mouth of the Ybbs in 2005 before the
constructon work.
In the lower section of the picture the grey water of Danube can
be seen. |
Redevelopment was made possible by purchasing 3.8 hectares of
agricultural land and through the contribution of additional land
areas by the municipality of Ybbs and the Republic of Austria. 80,000 m³
of earth was excavated and environmentally
valuable tree populations were able to be preserved. The
construction work lasted about one year and on 5 March 2007 water
was first let into the new zone.
|
simplified Grafic of the new
mouth
of river Ybbs- former shape in small picture
(© Andreas Bachmayr) |
|