Sustainable management of hydropower plants
- evn naturkraft operates 63 small hydropower plants and five pump storage plants in the Austrian provinces of Lower Austria and Styria. The design of the projects and operation of these plants are based on and comply with all applicable legal regulations and existing directives, rules and guidelines. Included here, among others, is the implementation of measures required by the National Water Management Plan (“Nationaler Gewässerbewirtschaftungsplan, NGP) to meet the EU’s Water Framework Directive. We are also involved in various scientific projects, like research on fish bypasses, and deal with current aquatic-ecological issues, for example on sediment management. Click here for further information.
Fish bypasses
- As part of the National Water Management Plan, we have installed numerous fish bypasses at our hydropower plants in line with current guidelines. Various types of bypasses and lifts are used, depending on the location, and their installation is supervised by ecological construction managers. Completion is followed by a separate monitoring programme to oversee the equipment’s functional effectiveness. Additional fish lifts are in planning for our existing hydropower plants, and separate lifts and bypasses are included in the planning for all new plants.
Additional projects include the operation of three ecologically important fishing areas by the EVN Fish Friends to support sustainable fisheries management. This helps to protect attractive recreational areas and make fish habitats more sustainable. Together with the support of experts, the EVN Fish Friends adjust their management concept and stock requirements for each body of water annually to reflect current developments. Their activities reflect our vision of natural, gentle, future-oriented water management.
Sediment management
- Roughly 70% of our small hydropower plants are so-called diversion plants. Their artificial corridor system naturally reduces the sedimentation problem to a minimum. On the one hand, the related weir systems generally have a low drop height. On the other hand, the outflow width at high water levels is opened as protection against flooding and to ensure and improve the continued flow of sediment.
Sediment management is also a central issue for the new construction and revitalisation of small hydropower plants. Recently revitalised projects were equipped with high-performance bottom outlet protection that is integrated in the automatic weir management. This outlet protection is lifted when the water reaches a certain level to allow debris to pass.
Dam safety
The dams operated by EVN are supervised by the Austrian Water Authority based on the Water Rights Act (“Wasserrechtsgesetz”) and managed in accordance with these guidelines. Applicable regulations define the responsibilities for local dam operators and guards, regular reporting to the authorities, and manual measurement by certified experts from a commission installed by the responsible federal ministry. The most important parameters for the dams are monitored automatically and any limit violations are reported to the plant control room in real time.