A view of the completed Life Traisen project: the renaturalized river meanders through the green countryside.

LIFE+ Traisen: From a straightened riverbed to a new wetlands habitat

Renaturation of the Traisen

LIFE+ Traisen - Austria's largest renaturation project has transformed the lower reaches of the Traisen near the Danube power plant in Altenwörth into a diverse riparian landscape. Between 2009 and 2019, a near-natural river course with diverse riparian areas was completely recreated. Many animal and plant species have already colonized it and numerous endangered animal and plant species have also found a new home here. The river landscape will now continue to develop undisturbed in a natural way.

Project profile

The Traisen is one of the largest rivers in Lower Austria. During the construction of the Danube power plant Altenwörth from 1973 to 1976, the Traisen was extended by 7.5 km and today flows downstream of the power plant. The riverbed ran in a straight line and uniformly through the floodplain between Traismauer and Zwentendorf. Thanks to the LIFE+ Traisen project, the straightened course has been broken up. The mouth of the Traisen into the Danube was completely recreated.

The new Traisen: a view of the floodplain landscape from above. You can see an alluvial pond in which the clouds are reflected, a small wood and the Traisen meandering through the landscape.

Project overview LIFE+ Traisen

The LIFE+ project implemented measures in the area between the Danube and the former Traisen Canal, creating a completely new Traisen river with surrounding riparian zones and a large estuary zone on the Danube. The water of the Traisen was diverted into this new riverbed around the Altenwörth power station. The old channel remained in place to provide relief during major floods and as still water. The project created the NEW lower course of the Traisen, which is not a revitalization of an old section of the river, but a new creation of dynamic river and floodplain habitat.

An overview of the Traisen project. The map of Austria shows roughly where the LIFE Traisen project is located.

LIFE+ Traisen - new life in the floodplain

Summary: Objectives and results

  • Maximum possible protection of existing valuable natural areas in the floodplain,
  • no negative changes to the flood or groundwater situation for local residents: Groundwater conditions will only be slightly altered in the vicinity of the Traisen. Groundwater uses such as wells are not affected.
  • Creation of a meandering river that can continue to develop dynamically in the future and offer new watercourse habitats.
  • Creation of diverse structures in the transition area between water and land on the banks of the new Traisen.
  • Creation of still waters, enrichment of the floodplain through water diversity and
  • Creation of a flood foreland with frequently flooded sites along the new course of the river. The site conditions for the development of the soft floodplain, especially the silver willow floodplain, are given here.
  • Increasing the proportion of floodplain and riverine habitat, which currently accounts for only 6 % of the Natura 2000 site as a whole.
  • Fish-passable linking of the floodplain and individual backwaters with the new Traisen river.
    Continuous fish passability of the new Traisen river: This will sustainably promote the fish fauna of the Danube, the Traisen river and the wetlands. At least 30 fish species will benefit from this. These include 15 Annex II species in the area.
Between 2009 and 2019, a new floodplain landscape was created on the Traisen. The picture shows the renaturalized Traisen from above. You can see not only the river, but also an alluvial forest.

VERBUND took on the project management and the majority of the costs. The EU supported the project to a large extent with funding from the EU LIFE+ Nature and Biodiversity Fund.

Other funding partners: Office of the Lower Austrian Provincial Government, Federal Ministry of Agriculture, Regions and Tourism, Lower Austrian Landscape Fund, Lower Austrian Provincial Fisheries Association, viadonau and with the support of the Augustinian Monastery of Herzogenburg and the Grafenegg Forestry Administration. The companies Energie AG, KELAG and VKW, which are entitled to purchase electricity from the Altenwörth power plant, are also involved. 

LIFE+ is an EU funding program to support nature conservation projects in Natura 2000 areas. The Natura 2000 network of protected areas is intended to help preserve the diversity of wild animal and plant species and habitats throughout Europe. The LIFE+ project Traisen contributes significantly to the improvement of the Natura 2000 area.