Overview of typical compensation measures and results of the monitoring campaign on the Upper Rhine at two HPPs

Transcription

1 Overview of typical compensation measures and results of the monitoring campaign on the Upper Rhine at two HPPs / FIThydro, Augsburg / Jochen Ulrich

2 Overview Upper Rhine HPP Rheinfelden and Ryburg-Schwörstadt (Average discharge Upper Rhine: 1030 m³/s) HPP Ryburg-Schwörstadt HPP Rheinfelden Basel Lake Constance 2

3 Overview Upper Rhine HPP Ryburg-Schwörstadt (max m³/s, 120 MW, production: 760 Mio. kwh/a) 3

4 In total 17 compensation measures (to get new approval / no technical changes at the HPP) B. Karrer

5 Overview Upper Rhine HPP Rheinfelden (max m³/s, 100 MW, production: 600 Mio. kwh/a) 5

6 Former HPP Rheinfelden Construction: biggest river power plant at that time // Main changes and impacts of new HPP Higher Water level +1,4m -> changes in hydraulics and ground water Loss of rock formation and habitat 6

7 Rheinfelden hydro power projekt Overview after construction / Overview fishways In total more than 80 compensation measures Roughened fischway Near-nature water course Vertical-Slot fishway 7

8 Overview compensation measures Examples will be shown in the presentation Fish passage (technical or near-nature fishways) Residual flow / Minimum flow Reconnecting oxbows, flood plains and small tributaries Renaturation Structural diversity of the shore and the river bed Specific measures to the protection of species Ground water Cultural Heritage Landscape / Recreation 8

9 Fish passage / Minimum flow / Habitat structures Ecological functions of the near-nature water course / Separate turbine for minimum flow purposes Separate turbine 30m³/s to ensure minimum flow on the rocks (to save spezialised species of moss ) (positive results in the last monitoring period!) Ecological functions: Riffles built out of gravel (spawning ground for common nase and barbel) Pools with gravel banks (habitat for different species) Deeper flow path (to ensure fish passage) Ecologically effective habitat structures (Gravel islands, rootstocks, trees, ) 9

10 Fish passage HPP Ryburg-Schwörstadt Two entrances with connection to the river bed and attraction flow 300 kw turbine / electricity + attraction flow 3D Graphic- Tailrace HPP Ryburg-Schwörstadt The attraction flow is generated by the discharge of a separately built 300 kw - turbine 10

11 HPP Rheinfelden Results of fish counting Fish passage Upper Rhine compared with the results of the and fish countings in Rheinfelden Quelle: Guthruf 2017 Quelle: Aquarius

12 Comparison of the results of the Rheinfelden fish counting with the counting 2005/2006 Upper Rhine, total number of species 12 The counting showed almost the same results like the counting Quelle: Aquarius 2013

13 Results fish counting Length of the registered fish (logarithmic diagram) Quelle: Aquarius

14 Comparision of the migrating species in the two fishways (left: water course, right: vertical slot) Near-nature water course: 34 species Vertical slot: 24 species Different abundance of species Quelle: Aquarius

15 Fish passage HPP Rheinfelden Fish counting - summary High number of migrating fish Very high number of species Abundance of rare species has significantly grown No selectivity Target species are present Similar results at the HPP Ryburg-Schwörstadt 15

16 Structural diversity of the shore and the river bed Gravel deposits / 1500 m³ every two years 16

17 Structural diversity on the shore and in the river bed 17 Quelle: Aquarius 2018

18 Structural diversity of the shore and the river bed Gravel deposits Objectives: Spawning ground, reactivation of sediment transportation Results monitoring: More gravel on the river banks and the river bed: But only few greylings in the initial feeding stage Spawning ground only in small quantities, gravel is eroded within short time Optimization of the measures: Find a better site Coordination on the whole Upper Rhine 18

19 Structural diversity of the shore and the river bed Artificial erosion of river banks 19 Quelle: Aquarius 2018

20 Structural diversity of the shore and the river bed Artificial erosion of river banks Objectives: Structure, small bays, trees as habitat Results monitoring: Small scale gravel deposits Greylings an barbels Optimization of the measures : none From time to time: remove vegetation 20

21 Reconnecting flood plain (Aue Wallbach) 21 Quelle: Aquarius 2018

22 Reconnecting flood plain (Aue Wallbach) Objectives: Dynamic, Structure, new oxbow, more habitats and retreat areas for juveniles and small species Results of monitoring: Sedimentation in the upper part, no more oxbow, but now backwater High fish density and many species high improvement Valuable retreat area and habitat for juveniles and small species Optimization of the measures: Backwater very valuable no measure to ensure reactivation of oxbo If sedimentation goes on take some measures to ensure the backwater habitat. 22

23 HPP Rheinfelden Monitoring vegetation 2013: Succession area 2016: More vegetation on the Succession areas Quelle: Ruess

24 HPP Rheinfelden Monitoring vegetation Results total species total species: 2010: : : 335 Highest level in succession areas and meadows Quelle: Ruess

25 HPP Rheinfelden Monitoring vegetation Results total number of endangered species (CH) Endangered species (CH): 2010: : : 30 Highest level in succession areas and meadows Quelle: Ruess

26 Results landscape slightly improved in the whole perimeter Low quality High quality Low quality Medium quality Quelle: Ruess

27 Results landscape slightly improved in the whole perimeter But also some places with lower quality Low quality High quality Quelle: Ruess

28 Monitoring HPP Rheinfelden Birds Goosander family close to the rock formation Great Crested Greep is breeding at the intake of the near-nature water course Quelle: Ruess

29 Monitoring HPP Rheinfelden Birds Artificial erosion sites are breeding places for the kingfisher 29

30 Compensation measures at HPP Rheinfelden and HPP Ryburg-Schwörstadt Summary The results in upstream migration, vegetation and landscape are very good. Most of the results in fauna are good as well, some of the measures probably take some time to reach full ecological function. Most of the measures to improve the structural diversity of the shore and the river bed are very successful: i.e. artificial erosion, trees, oxbows/backwater. High fish density in these places. Finding the right place for gravel deposits that result in spawning grounds for greylings seems to be difficult. Overall the compensation measures at the HPP Rheinfelden and Ryburg- Schwörstadt are very successful and improve the habitat of terrestrical and aquatic species significantly. 30