PROJECT DESCRIPTION
BACKGROUND
The Tyrolean Lech River, with its huge banks of gravel and broad zones of lowland riparian forest, is among the last rivers in the northern Alps that remain more or less in a natural state. For over 60 km, the highly braided (multi-channelled) river occupies a gravel bed that is up to 100 m wide in parts. The river’s course is constantly changing due to erosion and deposition. In Austria, including the border stretch with Germany, its dynamically braided course forms large-scale gravel and sand bars, and it still features unimpaired wild stretches. It is among the most threatened type of landscapes in Central Europe.
Floods and increasing pressure from human activities in the valley, however, have necessitated hydrological regulation measures. In certain sections these hydrological works have severely narrowed the riverbed. The construction of debris traps across the streams and growing exploitation of gravel have also contributed to a deepening of the riverbed and a lowering of the water table. The consequent disappearance of flooding and forests that are regularly submerged has adversely affected numerous species associated with gravel banks, including the German tamarisk (Myricaria germanica), the pink-winged grasshopper (Bryodema tuberculata) or the little ringed plover (Charadrius dubius).
From 2001 to 2007 the Tyrolean Lech Natura 2000 site was the focus of a LIFE project, Wild River Landscape Tyrolean Lech (LIFE00 NAT/A/007053). The project was a first successful step towards the reintroduction of natural dynamics into the river habitat. Continuation of works, however, is required to ensure the lasting success of habitat and species conservation.
OBJECTIVES
The LIFE Lech project aimed to conserve the natural dynamics of the Lech river system and surrounding riparian landscapes, along with its characteristic habitats and species. Specifically, it aimed to protect and develop the dynamically shaped gravel bars, which have been declining since the Lech regulation in the 19th century. Bank stabilisation structures would be removed, the river widened, side streams created and groynes shortened, thus affording spaces for the river to redevelop its natural dynamics. The upper reaches, in particular, possess great potential for the development of the gravel bars and pioneer habitats, which provide necessary living conditions for several highly specialised and endangered species.
The project also aimed to stop the deepening of the river bed and thus stabilise groundwater levels. This measure was expected to preserve the surrounding riparian landscape along with Alpine river habitats and alluvial forest priority habitat and species, such as the Siberian bluet (Coenagrion hylas), the stone crayfish (Austropotamobius torrentium), the northern crested newt (Triturus cristatus) and the European bullhead (Cottus gobio).
Another goal was to improve the way the visitors are managed in the area. Better and targeted information and awareness raising should help protect the breeding areas of disturbance-sensitive bird species (e.g. common sandpiper and little ringed plover) and at the same time increase the acceptance of the Natura 2000 network of sites among local people.
RESULTS
The LIFE Lech project team helped restore the natural dynamics of the Lech river system and surrounding riparian landscapes, by restored 13 river sections (12 in Austria and 1 in Germany). They implemented a range of measures, including removal of bank stabilisation structures, removal or shortening of groynes, river widening, and the creation of side streams. In total, significant new space was established for the river to re-create its natural dynamics: the creation of around 14 km of "soft" banks resulted in the development of 23 ha of new, dynamically-shaped river areas.
On 7.1 ha, new gravel habitats were created in favour of common sandpiper (Actitis hypoleucos) and little ringed plover (Charadius dubius). In connection with flood prevention, the potential of additional dynamic areas was increased by up to 62 ha. Near the municipality of Forchach, on the Lech River in Austria, the project team built an attractive new suspension bridge that enabled river widening by more than 200%.
In addition, the project team implemented an extensive set of species conservation measures:
- Creation of 38 water bodies for amphibians, to favour northern crested newt (Triturus cristatus), European tree frog (Hyla arborea), natterjack toad (Bufo calamita), and other species.
- Creation of 8 water bodies to provide habitat sites for the Siberian bluet (Coenagrion hylas).
- Creation of 4 additional tributaries (total length 2.6 km) for small fish, particularly European bullhead (Cottus gobio) and common minnow (Phoxinus phoxinus).
- Improved habitat for the scarce heath butterfly (Coenonympha hero) on 7.4 ha of riparian meadows.
- Revitalisation of dwarf bulrushes (Typha minima) on 4 sites through the plantation of 1 000 specimens.
The project team elaborated an integrated Natura 2000 Management Plan, which was discussed with stakeholders and adopted by the relevant authorities. For instance, it sets out plans for the continuous implementation of 175 individual measures in the Tiroler Lech Nature Park management plan. The After-LIFE plan puts in place a framework for the continuation and maintenance of these measures.
Various communication and networking activities accompanied the restoration effort. These included the production of 17 information boards, a touring exhibition, a leaflet, a new edition of the "Lech River Experience Guide", a tilt-effect postcard, and five short films. In addition, the project team organised 40 excursions and 11 action/event days, gave 17 project presentations, and participated in an international Wild River Symposium. They provided continuous visitor information at the Nature Park house (about 8 000 visitors a year), and they built a visitor facility near the new suspension bridge at Forchach with a rest area and fireplace, playground and information boards.
Further information on the project can be found in the project's layman report (see "Read more" section).