Offshore wind farms in the Belgian part of the North Sea State of the art after two years of environmental monitoring Edited by Steven Degraer Robin Brabant 2009 Royal Belgian Institute for Natural Sciences Management Unit of the North Sea Mathematical Models Marine Ecosystem Management Section in collaboration with II Commissioned and produced in 2009 by: Royal Belgian Institute for Natural Sciences (RBINS) Management Unit of the North Sea Mathematical Models (MUMM) www.mumm.ac.be Edited by: Steven Degraer ([email protected]) Robin Brabant ([email protected]) Cover photo: The first phase of the C-Power wind farm on the Thorntonbank (photo Jan Haelters/RBINS) Status draft final version revised version of document confidential Available in English Dutch French This report should be cited as: Degraer, S. & Brabant, R. (Eds.) (2009) Offshore wind farms in the Belgian part of the North Sea: State of the art after two years of environmental monitoring. Royal Belgian Institute for Natural Sciences, Management Unit of the North Sea Mathematical Models. Marine ecosystem management unit. 287 pp. + annexes. If a separate chapter is cited, the authors and the titel of that chapter need to be mentioned. If you have any questions or wish to receive a digital version of this document, please send an e-mail to [email protected], quoting the reference, or write to: MUMM 100 Gulledelle B–1200 Brussels Belgium Phone: +32 2 773 2111 Fax: +32 2 770 6972 http://www.mumm.ac.be/ Acknowledgements This research is financed by C-Power nv and Belwind nv, in fulfillment of the environmental monitoring program of their environmental permits. The authors want to thank C-Power and Belwind for their willing cooperation. This monitoring exercise benefited from the use of the research vessel Belgica (operated by the Belgian Navy under charter of the RBINS), the research vessel Zeeleeuw (operated by the Flanders Institute of the Sea) and the observation aircraft of RBINS for collecting the necessary data at sea. Critical remarks to parts of earlier versions of this report were received from R. Brabant, S. Degraer, M. Di Marcantonio, G. Pichot, T. Jacques, B. Rumes, S. Vandendriessche, G. Van Hoey and L. Vigin. III Table of contents Chapter 1 Degraer S., Brabant R. & Partnership (2009) Executive Summary: The monitoring results in a nutshell. pp. 1-11 Chapter 2 Brabant R., Degraer S. & Partnership (2009) A brief introduction to offshore wind farms in the Belgian part of the North Sea. pp. 13-16 Chapter 3 Haelters J., Norro A. & Jacques T.G. (2009) Underwater noise emission during the phase I construction of the C-Power wind farm and baseline for the Belwind wind farm. pp. 17-37 Chapter 4 Kerckhof F., Norro A., Jacgues T.G. & Degraer S. (2009) Early colonisation of a concrete offshore windmill foundation by marine biofouling on the Thornton Bank (southern North Sea). pp. 39-51 Chapter 5 Reubens J., Degraer S. & Vincx M. (2009) The importance of marine wind farms, as artificial hard substrates, on the North Sea bottom for the ecology of the ichthyofauna fish. pp. 53-60 Chapter 6 Reubens J., Vanden Eede S. & Vincx M. (2009) Monitoring of the effects of offshore wind farms on the endobenthos of soft substrates: Year-0 Bligh Bank and Year-1 Thorntonbank. pp. 61-91 Chapter 7 Vandendriessche S., Hostens K. & Wittoeck J. (2009) Monitoring of the effects of the Thorntonbank and Bligh Bank windmill parks on the epifauna and demersal fish fauna of soft-bottom sediments: Thorntonbank: status during construction (T1), Bligh Bank: reference condition (T0). pp. 93-150 Chapter 8 Vanermen N. & Stienen E. (2009) Seabirds & offshore wind farms: monitoring results 2008. pp. 151-221 Chapter 9 Brabant R. & Jacques T.G. (2009) Research strategy and equipment for studying flying birds in wind farms in the Belgian part of the North Sea. pp. 223-235 Chapter 10 Haelters J. (2009) Monitoring of marine mammals in the framework of the construction and exploitation of offshore wind farms in Belgian marine water. 237-266 Chapter 11 Di Marcantonio M. (2009) Seascape and socio economic study: preparatory year. pp. 267-273 Chapter 12 Degraer S., Brabant R. & Partnership. (2009) Recommendations for a future monitoring of wind farms in Belgium’s marine waters. pp. 275-279 Chapter 13 Degraer S., Brabant R. & Partnership. (2009) Conclusions: the main messages…pp. 281- 285 Annexes pp. 287 Annex 1. Systematic species list of hard substrate epifauna and –flora Annex 2. Systematic species list of soft substrate macrobenthos Annex 3. Bubble plots median grain size (µm) 2008 Annex 4. Simper analyses Annex 5. Photographs of beam trawl catches Annex 6. Systematic species list of the demersal fish fauna Annex 7. Systematic species list of soft substrate epibenthos Annex 8. Summarizing maps – densities of demersal fish and epibenthos per fish tracks Chapter 1. Executive summary: the monitoring results in a nutshell S. Degraer, R. Brabant & Partnership Management Unit of the North Sea Mathematical Models (MUMM), Gulledelle 100, Brussels, Belgium Photo Alain Norro / RBINS 2 S. Degraer, R. Brabant & Partnership 1.1. Introduction The European directive 2001/77/EG presently imposes each member state a target figure for its contribution to the production of electricity from renewable energy sources that should be achieved by 2010. For Belgium, this target figure was set at 6 % of the total energy consumption. Since a Royal Decree on 17 May 2004 assigned a zone for the production of electricity in the Belgian part of the North Sea (BPNS), two companies, C-Power and Belwind, were granted a permit to build and exploit a wind farm on the Thorntonbank (60 turbines, 300 MW) and Bligh Bank (110 turbines, 330 MW), respectively. A third company, Eldepasco, initiated the environmental permit procedure in 2009. The permits include an obligation to establish a monitoring programme (1) to ensure the ability to mitigate the negative effects of the concerned activities (or even halt them in case of extreme damage to the marine ecosystem) and (2) to acquire an assessment and understanding of the environmental impact of offshore wind farms to support policy, management and the design of future offshore wind farms. The first phase of the monitoring programme started the year before the anticipated construction of the first wind turbines at the Thorntonbank (i.e. 2005) and will last for six years to allow the identification and quantification of possible effects. At the end of this first phase, an overview and discussion of the monitoring activities and outcomes are planned between MUMM, its monitoring partners and the wind farm industry. This workshop will be the first thorough evaluation of possible impacts of marine wind farms in Belgian waters. 1.2. Monitoring objectives This report presents a compilation of the results of the monitoring activities in the year 2008. The report covers: 1. the evaluation of the appropriateness of the selected reference sites and reference conditions for both the C-Power and the Belwind project, 2. the various environmental data under surveillance, with an evaluation of the preliminary impacts due to the construction of six turbines at the Thorntonbank (C-Power project: comparison with data collected in 2005) 3. advices for future monitoring at the level of technicalities, scientific design, as well as research focus and strategies (C-Power and Belwind project). 1.3. Monitoring strategy 1.3.1. Environmental assets and monitoring design The monitoring programme targets physical (i.e. hydrodynamics, underwater noise and electromagnetic fields1), biological (i.e. hard substrate epifauna, hard substrate fish, soft substrate 1 The monitoring programme of each wind farm foresees two measurements of the electromagnetic fields (EMF) produced by the electrical cables in the wind farm and to the shore: once during the procution of a pilot phase, a second time when the entire park is completed and in production. EMF measurements at the Thorntonbank were postponed to 2009, as in 2008 only two of the six turbines of the pilot phase were in production. A condition in the permit states that all cables need to be at least 1 m below the seabed at all time for reasons of maritime safety. The resultant physical barrier is expected to reduce environmental impact on organisms that are influenced by EMF. Initial studies by COWRIE (Collaborative Offshore Wind Research into the Environment) have demonstrated that the EMF of submerged cables can influence elasmobranches. However, due to a high variation in response at the level of individuals and species, no straightforward impact of EMF could be quantified. Further research in this field is ongoing and MUMM awaits the conclusions of this study to fine tune its future activities related to EMF. Chapter 1. Executive summary 3 macrobenthos, soft substrate epibenthos and fish, seabirds, marine mammals), as well as socio- economical (seascape perception) aspects of the marine environment. MUMM coordinates the monitoring activities and conducts the studies on underwater noise, hard substrate epifauna and fish, seabird radar detection, marine mammals, hydrodynamics and electromagnetic fields. MUMM further collaborates with different institutions to complement its expertise in the following domains: seabirds (INBO), soft substrate epibenthos and fish (ILVO), soft substrate macrobenthos and hard substrate fish (Marine Biology Section of Ghent University), underwater noise (Renard Centre of Marine Geology of Ghent University). In general, the monitoring programme follows a Before-After/Control-Impact (BACI) design, in which the changes within the concession areas during construction and exploitation of the wind farms are and will be compared with the state before the construction started (i.e. reference condition) and the state of highly similar, though non-impacted reference sites. Such a design allows one to objectively quantify possible impacts due to the construction and exploitation of the wind farms once the natural variability both in space and time is duly taken into account.