1. Managing the Environmental Impacts of Hydropower Scottish R&D Programme IWRM Stockholm November 2008

2. Overview of the Presentation Background Background R&D Needs and Scope R&D Needs and Scope Methods & Techniques Methods & Techniques Conclusions Conclusions

3. Limited hydro development late 19th early 20th Century Limited hydro development late 19th early 20th Century NOSHEB formed in 1943 to provide electricity to highland communities NOSHEB formed in 1943 to provide electricity to highland communities NOSHEB were privatised in 1989 and became part of SSE in 1998 NOSHEB were privatised in 1989 and became part of SSE in 1998 SSE operate 72 hydropower stations (incl. 84 major dams & hundreds of intakes) SSE operate 72 hydropower stations (incl. 84 major dams & hundreds of intakes) We generate around 3,200 GWhrs/yr ( 40% of current UK renewables) We generate around 3,200 GWhrs/yr ( 40% of current UK renewables) SSE Hydropower Generation Mitigation was highly developed for the time Mitigation was highly developed for the time These measures focussed largely on salmon These measures focussed largely on salmon A new large storage scheme currently being commissioned A new large storage scheme currently being commissioned

4. Examples of Existing Mitigation There is already significant mitigation on our schemes There is already significant mitigation on our schemes These include: These include: compensation flows compensation flows ‘hands off’ flows ‘hands off’ flows freshets freshets fish passes fish passes fish counters fish counters smolt screens smolt screens smolt traps smolt traps tailrace screens tailrace screens adult fish traps adult fish traps a hatchery a hatchery

5. Why does Hydropower matter? Plays an important role in combating climate change: Plays an important role in combating climate change: very low CO 2 lifetime emissions very low CO 2 lifetime emissions storage schemes help manage intermittent supplies (e.g. wind) storage schemes help manage intermittent supplies (e.g. wind) European targets have been set for renewable energy European targets have been set for renewable energy UK & Scottish Governments have set ambitious targets for renewable electricity and renewable energy UK & Scottish Governments have set ambitious targets for renewable electricity and renewable energy Any reduction in output from existing sites will inevitably be made up by fossil fuel fired generation Any reduction in output from existing sites will inevitably be made up by fossil fuel fired generation A recent Scottish Govt. sponsored study identified >650 MW of financially & environmentally viable new schemes A recent Scottish Govt. sponsored study identified >650 MW of financially & environmentally viable new schemes Balance of global environmental benefits vs. local environmental impacts Balance of global environmental benefits vs. local environmental impacts

6. WFD and Hydropower For waterbodies affected by large scale hydropower WFD has an objective of Good Ecological Potential (GEP) For waterbodies affected by large scale hydropower WFD has an objective of Good Ecological Potential (GEP) GEP is the best ecological outcome that can reasonably be achieved given the existing type and scale of use GEP is the best ecological outcome that can reasonably be achieved given the existing type and scale of use UK environment agencies are defining GEP in terms of the ‘alternative approach’ (see next slide) UK environment agencies are defining GEP in terms of the ‘alternative approach’ (see next slide) This means considering if ‘missing’ measures are consistent with the existing scale of use This means considering if ‘missing’ measures are consistent with the existing scale of use This approach is an admission that the basic science is not sufficiently well developed This approach is an admission that the basic science is not sufficiently well developed Even using this approach we are not able to fully define measures for some problems (e.g. sediment management) Even using this approach we are not able to fully define measures for some problems (e.g. sediment management)

7. Definition of GEP

8. R&D Needs and Scope¹ There is a general recognition that hydro- morphology is linked to ecology There is a general recognition that hydro- morphology is linked to ecology But a lack of empirical data means we are not able to predict the ecological effects of changes in hydro- morphology with any confidence But a lack of empirical data means we are not able to predict the ecological effects of changes in hydro- morphology with any confidence We want to be sure that any measures we implement really do work We want to be sure that any measures we implement really do work This will require: This will require: baseline hydro-morphology and ecological surveys baseline hydro-morphology and ecological surveys long term monitoring following any changes long term monitoring following any changes SSE has initiated a number of projects to begin collecting this data SSE has initiated a number of projects to begin collecting this data

9. Collaborative R&D We are in the process of setting up a collaborative research programme We are in the process of setting up a collaborative research programme We hope that collaboration will: We hope that collaboration will: pool expertise and resources pool expertise and resources build confidence with regulators and stakeholders build confidence with regulators and stakeholders deliver a better research programme deliver a better research programme Partners include the Scottish EPA and other research and academic organisations Partners include the Scottish EPA and other research and academic organisations The initial aim is to fund a long term (5yr+) post to co-ordinate the research and support publication of peer reviewed papers The initial aim is to fund a long term (5yr+) post to co-ordinate the research and support publication of peer reviewed papers

10. Site Based Methods¹ Geomorphic conditions: Geomorphic conditions: Grain Size Distribution Grain Size Distribution Armouring Armouring Sediment Deficits Sediment Deficits Material finer than 64 mm (gravel) missing from many areas Material finer than 64 mm (gravel) missing from many areas Clearly some very degraded rivers but tributary inputs rapidly improve conditions Clearly some very degraded rivers but tributary inputs rapidly improve conditions Natural rivers are also armoured – need for reference conditions Natural rivers are also armoured – need for reference conditions

11. Site Based Methods² Input data to hydraulic models and equations to calculate critical discharges Input data to hydraulic models and equations to calculate critical discharges This can identify geomorphically effective flows This can identify geomorphically effective flows Discharges needed to mobilise current beds (coarse, stable and armoured) can be extremely large (<700 m 3 s -1 ) Discharges needed to mobilise current beds (coarse, stable and armoured) can be extremely large (<700 m 3 s -1 ) Clear need to look at parallel flow restoration and sediment augmentation Clear need to look at parallel flow restoration and sediment augmentation Links to aerial sediment size mapping Links to aerial sediment size mapping

12. Aerial Photography Techniques 1. Aerial grain size maps 2. Aerial bathymetry (depth) maps

13. Sediment Grain Size Maps High resolution digital aerial photography (e.g. 3cm resolution) Ground truth data (grain size samples) Aerial photo-sieving Can be performed post-survey. Ground samples / geo- referencing not strictly necessary. Can be performed on back- dated imagery. Ground data Requires images and ground samples to be geo-referenced with differential GPS. Cannot be performed on back-dated imagery. Calibrated aerial grain size maps OR

14. Bathymetry (Depth) Maps High resolution digital aerial photography (e.g. 3cm resolution) Ground truth data (river depth profiles) Ground Data Requires images to be geo- referenced with differential GPS. Depth profiles of river must be taken at site of geo-referencing. Profiles must be taken on day of aerial survey to ensure that river level is same as imagery. Bathymetry maps cannot be produced without accurate ground control or river level data. Calibrated aerial bathymetry maps

15. Habitat Maps Aerial grain size maps Aerial bathymetry maps Salmonid habitat map Salmonid habitat requirements (e.g. optimal spawning = grain size of 25- 60mm and depth of 250-500mm) Other Species? Requires habitat requirements to be defined

16. Example: Salmon Habitat Map Optimal spawning habitat Sub-optimal spawning Mixed juvenile (fry, parr) Passageway (torrent, glide, pool) Not useable (eg. too shallow) Traditional walkover survey (Cragg-Hine & Hendry, 1997) Computer-generated habitat map

17. Detailed Habitat Map Optimal spawning habitat Sub-optimal spawning Mixed juvenile (fry, parr) Passageway (torrent, glide, pool) Not useable (e.g. too shallow)

18. Salmon Smolt Productivity Eggs: c. 5000 eggs per female 100,000 Fry 0+: 10% survival egg to fry 10,000 Parr 1+: 33% survival fry to parr 3,300 Smolt 2+: 50% survival parr to smolt 1,650 Smolt trap data (Figures used are for illustrative purposes only)

19. Conclusions There is a clear need to improve our understanding of the links between hydro–morphology and ecology There is a clear need to improve our understanding of the links between hydro–morphology and ecology We are attempting to combine traditional ground based methods with aerial survey / remote sensing techniques We are attempting to combine traditional ground based methods with aerial survey / remote sensing techniques The initial results look very positive The initial results look very positive The next steps will be to: The next steps will be to: compare habitat map based predictions with field data (e.g. smolt numbers) compare habitat map based predictions with field data (e.g. smolt numbers) try to develop habitat maps for other flora / fauna try to develop habitat maps for other flora / fauna try to develop the aerial techniques further (e.g. flow velocity) try to develop the aerial techniques further (e.g. flow velocity) If the method works we will apply it at more sites and revise our operational practice where we can If the method works we will apply it at more sites and revise our operational practice where we can