Barrow Offshore Wind Farm Post Construction Monitoring Report
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Barrow Offshore Wind Farm Post Construction Monitoring Report First Annual Report 15 January 2008 This Post Construction Monitoring Report has been prepared by Barrow Offshore Wind Ltd. as part of the environmental monitoring of Barrow Offshore Wind Farm. This report describes the first year of post-construction environmental monitoring in 2006-2007 after construction of the wind farm. The wind farm became operational in July 2006. The report is prepared to comply with the FEPA licence conditions. Technical surveys and studies are the basis of this Post Construction Monitoring Report. Full unedited copies of the environmental studies and findings can be found in the attached Appendi- ces. They are available on CD only and are attached to this report. Requests for additional copies of this report should be made to: Barrow Offshore Wind Ltd. c/o DONG Energy AC Meyers Vænge 9 DK-2450 Copenhagen SW Denmark Att. Trine H. Sørensen The report and appendices may also be downloaded from Barrow Offshore Wind Ltd.’s website: www.bowind.co.uk. No part of this publication may be reproduced without written permission from Barrow Offshore Wind Ltd. This report has been written by NIRAS Consulting Engineers and Planners A/S, based on reports and surveys produced by a wide team of consultants. 18/12-07 18/12-07 19/12-07 20/12-07 DATE ÆO. BHH HHK KURJE TRIHS NAME DATE ÆO. NAME REV. DESCRIPTION PREPARED CHECKED REVIEWED APPROVED FLS-034378 DOC. NO. © Barrow Offshore Wind Ltd. POST CONSTRUCTION MONITORING REPORT i TABLE OF CONTENTS 1. EXECUTIVE SUMMARY ......................................................................................................3 2. INTRODUCTION...................................................................................................................5 3. ENVIRONMENTAL MONITORING SPECIFICATIONS........................................................7 4. RESULTS, OFFSHORE MONITORING .............................................................................10 4.1 Fisheries ...............................................................................................................10 4.1.1 Conditions ............................................................................................10 4.1.2 Monitoring Methods..............................................................................10 4.1.3 Results and conclusions.......................................................................11 4.2 Benthic and Sediment Contaminant Survey .........................................................16 4.2.1 Conditions ............................................................................................16 4.2.2 Monitoring Methods..............................................................................16 4.2.3 Results and Conclusions......................................................................18 4.3 Operational Underwater Noise .............................................................................21 4.3.1 Conditions ............................................................................................21 4.3.2 Monitoring Methods..............................................................................21 4.3.3 Results and Conclusions......................................................................22 4.4 Oceanography ......................................................................................................24 4.4.1 Conditions ............................................................................................24 4.4.2 Monitoring Methods..............................................................................24 4.4.3 Results and Conclusions......................................................................25 4.5 Bathymetry, Seabed Morphology and Scour ........................................................26 4.5.1 Conditions ............................................................................................26 4.5.2 Monitoring Methods..............................................................................26 4.5.3 Results and Conclusions......................................................................26 4.6 Side Scan Sonar Survey and Archaeology...........................................................30 4.6.1 Conditions ............................................................................................30 4.6.2 Monitoring Methods..............................................................................31 4.6.3 Results and Conclusions......................................................................31 4.7 Birds .....................................................................................................................37 4.7.1 Conditions ............................................................................................37 4.7.2 Monitoring methods..............................................................................37 4.7.3 Objective 1 ...........................................................................................41 4.7.4 Objective 2 ...........................................................................................41 4.7.5 Objective 3 ...........................................................................................45 4.7.6 Objective 4 ...........................................................................................55 5. CONCLUSIONS..................................................................................................................56 6. REFERENCES....................................................................................................................57 APPENDICES: APPENDIX 1: LICENCE REFERENCE 31744/07/1 – JULY 2007 APPENDIX 2: LICENCE REFERENCE 33069/07/1 – APRIL 2007 APPENDIX 3: MONITORING SPECIFICATIONS, SUBMITTED TO DEFRA IN OCTOBER 2005 APPENDIX 4: TECHNICAL MONITORING REPORTS ii POST CONSTRUCTION MONITORING REPORT 1. EXECUTIVE SUMMARY Barrow Offshore Wind Farm is the Environmental Impact Assess- with Amphiura preferring a finer located in the eastern Irish Sea ment. At the post construction sediment than Ophiura. near Barrow-in-Furness. The surveys no basking sharks were There are significant correlations transmission cable runs into More- detected. Concerning Thornback between the concentrations of a cambe Bay where it is connected to ray, 20 and 40 individuals were number of the metals, but not be- the National Grid transformer sta- collected at the surveys in Decem- tween metals and the grain sizes or tion in Heysham. ber 2006 and March 2007, respec- TOC. An analysis of the physical tively. They were detected both at The construction of Barrow Off- and chemical parameters and the the control site and within the wind shore Wind Farm took place be- communities present show that farm area. tween March 2005 and July 2006. grain size and TOC influence the The wind farm became operational Benthic and Sediment Contami- communities present, but no other in July 2006. nants Surveys: The grain sizes environmental variables have a across both the windfarm site and significant influence on the com- This document describes the envi- reference sites have generally munities. ronmental monitoring undertaken increased between 2004 and 2007. during the post construction phase Operational Underwater Noise: The Due to relatively consistent in 2006–2007. The environmental survey results indicate that there is changes taking place across the monitoring reported in this docu- a marginal increase in very low whole survey area, and that some ment should be seen as a con- frequency noise around individual of these changes took place, be- tinuation of the pre-construction wind turbines. This increase is fore construction of the windfarm and construction monitoring. Post- detectable to a range of approxi- began, it would appear that they construction monitoring activities mately 600m. The results from are natural fluctuations and proba- are made for a period of three measurements taken at ranges of 5 bly influenced by the general sedi- years after construction and will be m from an operational wind turbine ment movement patterns in the reported annually to the licensing indicate that the underwater noise Irish Sea. TOC levels have gener- authority, as described in the FEPA is unlikely to cause a behavioural ally decreased throughout the pe- licence. This is the first of three (avoidance) response in marine riod 2002 – 2007 across the survey post-construction monitoring re- fish and marine mammals in the area, again probably with little ports. region. influence from the construction or The environmental monitoring did operation of the windfarm. Oceanography: In all cases wakes not register major or unforeseen could be traced out to a distance of There have been changes in the environmental impacts during the at least 6–10 diameters distance benthic communities present first year of operation. The follow- downstream of each monopile (30– across the windfarm and its refer- ing paragraphs summarise the 50 m) and often a good deal fur- ence sites between the pre- and primary results from the monitoring ther, in the order of 100–200 m. post-construction surveys. Similar- programme. Bubble clouds entrained in the ity analysis shows that the sites wakes forming behind turbine mo- Fishery: Catches from inside the from 2004 as a group are more nopiles are traceable over even wind farm were compared to exter- similar to themselves than they are longer distances, as far as 200 m nal control sites. No significant to any of the sites sampled in and possibly