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Anja Skiple Ibrekk & Tor Simon Pedersen

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1 Anja Skiple Ibrekk & Tor Simon Pedersen
PRB Workshop on 'Annual Review and Research & Technology Integration’, Ghent, 4-5 Oct HMWBs - Methodology Used in the Provisional Article 5 Report of Suldal PRB and Future Challenges Anja Skiple Ibrekk & Tor Simon Pedersen Norwegian Water Resources and Energy Directorate

2 Outline of Presentation
Introduction to the Suldal River Basin; Examples of HMWBs in the Suldal PRB; The identification and designation process: Methodology used in 2004 (step 1 – 6); Challenges related to the methodology that will be used 2005 – 2009 (step 7 – 11); and Ongoing activities related to HMWBs.

3 Suldal PRB in Western Norway
Catchment area: 1461 km2 Large areas of pristine nature; Sparsely populated: 1.7 inhabitants/km2 One of Norway’s most famous Atlantic salmon rivers, known for especially large fish; Two large hydropower schemes (6 % of the total electricity production in Norway): 7550 GWh mean annual production; Largest reservoir in Norway – Blåsjø; and Extensive research in the catchment area

4 HMWBs in the Suldal PRB Potential HMWBs: 49 (of total 113 WBs)
Lakes/reservoirs: 16 (high water level fluctuations); Rivers: 33 (some river stretches almost dry in periods); Results still to be confirmed by local and regional authorities; and Expected reduction in number of HMWBs as a result of the final designation test. Photo: Arve Tvede

5 Suldal PRB - Risk of failing GES by 2015 (Lower part)

6 Suldal PRB - Risk of failing GES by 2015 (Eastern part)

7 Stream diversion, no bypass

8 Heavily regulated reservoir, Blåsjø, (140 meters drawdown, 3105 mill
Heavily regulated reservoir, Blåsjø, (140 meters drawdown, 3105 mill. m3)

9 Basis for designating HMWB
Based on CIS HMWB GD; A national GD has been developed; The overall strategy has been to include the uncertain cases (broad approach); to prevent unrealistic ambitions; considered to be more practical to go from ‘heavily modified’ to ‘natural’ than the opposite way; to get the uncertain cases included in a full designation test including economic assessment; lack of data at this stage (obligation to get more data on the uncertain cases).

10 What have been done so far: Step 1 - 6 (Article 5, 2004):
Delineation of water bodies; Indirect physical criteria has been developed based on knowledge of ecological impacts (indirect way to assess risk of not complying with GES); Linked existing national databases with the physical criteria; Undertaken first computer assisted screening in the Suldal PRB and other national pilots; and Provisional HMWBs identified in all of Norway.

11 The national GD based on criteria developed with the following considerations;
Winter drawdown in lakes/reservoirs; Low-flow conditions in rivers due to upstream abstractions and changes in retention time in reservoirs; Mixing of water from neighbouring rivers (inter-basin transfer); Changes in water temperature affecting ice cover and biota; and Changes in retention time in lakes affecting chemistry distribution in the lake, e.g. degree of eutrophication.

12 Main screening criteria (step 1- 6) to identify provisionally as HMWB
Changes in lake water level:+10 meters; Lakes with an active annual regulation zone: ± 3 meters; Change in the hydraulic load by factor of 5 or more (lakes); No-bypass stream diversion; the 75% criterion; All rivers where minimum environmental flow is required; River no longer covered with ice and winter temperatures always above +1 deg C (as a result of water intakes); Normal annual flow augmented more than 3 times (rivers); and Change in water flow more than 5 % per hour of maximum capacity of the hydropower plant (no peaking).

13 75% criterion for stream diversion
Designation of HMWB extends downstream until the catchment area for undisturbed flow has returned to at least 75% of the natural catchment area. 25% 50% ”Diversion Tunnel”

14 Challenges related to the methodology that will be used in 2005 – 2009 (step 7 – 11)
Restoration and mitigation measures; Beneficial objectives achieved by other means than hydropower; Estimation of costs of impacts on specified uses; MEP - maximum ecological potential; and GEP - good ecological potential.

15 Future challenges - 1 Step 7: Restoration measures necessary to achieve GEP ”New” ways of restoring; flash floods, especially adapted flow regimes, etc; Define ”significant adverse effects”; What scale are we working at ?; (WB, regional or national) Design and create micro habitats. What is significant and on wich scale are we working? A local (WB) 10% reduction in electricity production may not have significant adverse effect on the power plant, but on a national scale it will. The Guidline states that ”…will vary between sectors and will be influenced by the sosioeconomic priorities of the MS” and ” Effects can be determined at water body level, a group of water bodies, a region, a RBD or at national scale.” The ”significant adverse effect” will vary between types of hydromorphological changes within the sam WB. River hydropower plants generally closer to GES than ”stream diversions”?

16 Future challenges - 2 Step 8: Other means which are technically feasible, significantly better environmentally and not disproportionately costly Replace the electricity production by other renewable energy sources (wind, biomass), geothermal, energy saving? (long-term measure); Flexibility within the RBD (can reduced production at one location with sensitive ecology be compensated with increased production at another location?); and Assessing disproportionate cost (cost alternatives or cost-benefit). Flexibility within the licensing system: Allow a hydro power developer a less strict licensing regime in one WB exchange for removing HP-scheeme in a more vulnerable WB The six year iterative rewising of the RBMP will demand that a HP-scheeme is compared against the available altenatives at each cycle. Makes

17 Future challenges - 3 Step 10/11: Defining MEP & GEP
Finding closest comparable water body; Do existing mitigation measures apply?; Knowledge on impacts of mitigation measures lacking – transfer between basins?; and Is our hydropower licensing system in line with the WFD? The reference condition is defined by the ”closest comperable”. A river turned in to a lake should be compered to the closest lake of the same type. This could be difficult in some cases where this new lake type migth not excist naturally. Calls for a bit of modelling and expert judgements Guidline: ”MEP is the maximum ecological quality that coul be achieved foar a HMWB once all mitgating meassures, that do not have significantly adverse effect on the spesified uses or the wider environment, have been applied”

18 Future challenges - 4 Cost effective analyses of mitigation measures
Draft river basin management plan: Cost effective analyses of mitigation measures Hydromorphological parameters; Assessment of derogations (cost-benefit); and Integrate economy and ecology at WB level.

19 Ongoing and planned HMWB activities
The HMWB-hydropower group, next meeting in Nov 04 (FIN, UK, AU, GE, SWE, NO); Planned activities with Suldal PRB as case: Defining MEP/GEP methodology; Economic assessment related to HMWB; Focus area within the PRB network ?; and HMWB-workshop spring 2005.

20 Last slide…. Draft methodology –revisions are expected.
Important: Draft methodology –revisions are expected. Use the PRB to demonstrate the methodology and promote discussion. “Takk for meg!” (Thank you!) WFD


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