As already announced, we at WET – Wildwasser erhalten Tirol are now actively campaigning for the Ötztaler Ache and against all planned hydro power developments in Ötztal. In the following you will find an overview of what is going on there and why we are against it. Our top priority at the moment is the Tumpen-Habichen power plant as the construction works have already started – our petition to stop them can be found here.
The Ötz valley is the longest (side) valley in Tyrol and the Ötztaler Ache the longest river without any hydro power plants in Tyrol. Apart from the Brunauer weir, there is currently not a single cross river construction structure in the entire river Ötztaler Ache! Alarmingly enough, this is unique by now in Tyrol. The Ötztaler Ache is therefore ecologically continous and free to supply all of its water, bed load and nutrients to the Inn without obstacles. At the end of the further Ötztal are large glaciers: 13% of the catchment area of the river is glaciated. Due to the resulting snow melt, the river’s outflow fluctuates strongly over the year. In winter the average flow is less than 10m³ / s, in summer the daily average can be over 250m³ / s – and the sediment and bed load transport is accordingly high in summer.
The first ever hydro power plant at Ötztaler Ache
There are several hydropower projects in the planning stage which will have an impact on the Ötztaler Ache. A diversion hydro power plant is to be built between Tumpen and Habichen – the first power plant in the otherwise free-flowing Ache. Not only would the ecological passability and continuity of the Ötz be lost, but it will also affect the river sections below the planned power plant, which are classified as ‚unique‘ and ’sensitive‘. The approach of the project operators is particularly outrageous in this respect, as construction of the Tumpen-Habichen power plant has already begun in the midst of the chaos of the corona crisis – despite open legal questions, unresolved complaints and without a legally binding permit. We therefore call on the state of Tyrol to stop the construction work with immediate effect in order to guarantee fair legal proceedings. We also request to dismiss the power plant once and for all in order to preserve the unique stretch of river as a natural and recreational area and to protect the local residents! You can find more information here, and you can support our petition here:
… plus 7 more diversions!
Looking at the bigger picture, the plans for the Ötztal are outrageous: In addition to the diversion hydro power plant in Tumpen, 7 tributaries of the Ötztaler Ache are to be drained and diverted. All their water is supposed to be transferred to other valleys, meaning it will be absent from the Ötztal. These are:
- Schranbach, max. 1.2 m³/s, „Storage hydro power plant (HPP) Kühtai“
- Fischbach, max. 4.8 m³/s, „Storage HPP Kühtai“
- Winnebach, max. 2.7 m³/s, „Storage HPP Kühtai“
- Königsbach, max. 1.1 m³/s, „Expansion of HPP Kaunertal“
- Ferwallbach, max. 1.2 m³/s, „Expansion of HPP Kaunertal“
- Gurgler Ache, max. 29.0 m³/s, „Expansion of HPP Kaunertal“
- Venter Ache, max. 50.0 m³/s, „Expansion of HPP Kaunertal“
A total area of 341.2 km² would be lost from the catchment area of the Ötztaler Ache in the future (taking the gauge in Tumpen as a reference point). This corresponds to approximately 43% of the natural catchment area (785.5 km²). Forty-three percent!
A rough overview of the planned hydro power plants
In the far Ötztal, water intakes are planned on the Gurgler Ache and its tributaries (no. 1 in the map above) and on the Venter Ache (no. 2, see map). The (already existing) Kaunertal power station is a storage hydro power station. In its reservoir at Gepatsch the water of 10 different creeks is collected and then diverted through a pressure stollen towards Prutz (Inn). It is planned to expand all this by an additional reservoir lake in the Platzertal valley, which is supposed to receive water from the „natural tributaries“ of the Venter and Gurgler Ache. For this the construction of an approximately 23 km long tunnel is necessary.
The Ötztaler Wasserkraft GmbH (municipality of Ötz, municipality of Umhausen, Auer Beteiligungs GmbH, TIWAG-Tiroler Wasserkraft AG) is planning a diversion power plant with a reservoir in Tumpen (no. 4, see map). The water is to be diverted before the Achstürze with its significant gradient of a 77 m drop, and is to be be reintroduced to the stream bed at Huben. The „Citizens‘ Initiative Against Hydro Power Plant Tumpen“ fears above all for the safety of the local residents due to the increased risks of floods in Tumpen and Habichen. You can find information on all of their concerns on their website – and there are a lot of them!
Hydro power plant group Sellrain-Silz (HPP Kühtai)
The Sellrain-Silz hydro power plant (HPP) group is a pumped storage hydro power plant. An additional reservoir lake is supposed to be built here, to be filled with water diverted from the catchment area of the Ötztaler Ache and the Ruetz in the Stubai valley. The construction of an approx. 26 km long tunnel is necessary to divert the water to the new reservoir. On the Ötztal side three streams are affected: the Fischbach, the Schranbach and the Winnebach. In the Stubai valley the following streams are supposed to be diverted: Unterbergbach, Daunkogelfernerbach and Fernaubach. The water of the Unterbergbach in the Stubai Valley and the water of the Fischbach on the Ötztal side even have to be pumped up (!) to reach the elevation of the tunnel before it can be diverted to Kühtai.