COWRIE ScourSed-09 A Further Review of Sediment Monitoring Data Ben Carroll, Bill Cooper, Nicola Dewey, Peter Whitehead (ABP Marine Environmental Research Ltd) Tony Dolphin, Jon Rees, Adrian Judd (CEFAS) Richard Whitehouse and John Harris (HR Wallingford Ltd) Final Report March 2010 This report has been commissioned by COWRIE Ltd © COWRIE Ltd, 2010 Published by COWRIE Ltd. This publication (excluding the logos) may be re-used free of charge in any format or medium. It may only be re-used accurately and not in a misleading context. The material must be acknowledged as COWRIE Ltd copyright and use of it must give the title of the source publication. Where third party copyright material has been identified, further use of that material requires permission from the copyright holders concerned. ISBN: 978-0-9561404-8-7 Preferred way to cite this report: ABPmer Ltd et al. (2010) A Further Review of Sediment Monitoring Data. Commissioned by COWRIE Ltd (project reference ScourSed-09) Copies available from: www.offshorewind.co.uk E-mail: [email protected] Contact details: ABP Marine Environmental Research Ltd Suite B, Waterside House Town Quay Southampton SO14 2AQ Tel: +44(0)23 8071 1840 Fax: +44(0)23 8071 1841 A Further Review of Sediment Monitoring Data Table of Contents Page Table of Contents ..........................................................................................................i List of Tables and Figures............................................................................................iii Acronyms ................................................................................................................... vii Units...........................................................................................................................vii Executive Summary......................................................................................................1 1. Introduction.........................................................................................................2 1.1 Background....................................................................................................... 2 1.2 Project Objectives .............................................................................................. 2 2. Approach..............................................................................................................3 2.1 Overview .......................................................................................................... 3 2.2 Evidence Base ................................................................................................... 4 2.3 Structure of Data Review..................................................................................... 7 2.3.1 Suspended Sediment Concentration ................................................................ 7 2.3.2 Seabed Morphology....................................................................................... 8 2.3.3 Scour.......................................................................................................... 8 2.4 Data Review Issues ............................................................................................ 8 3. Review of Suspended Sediment Concentration ....................................................9 3.1 Background....................................................................................................... 9 3.2 Lynn and Inner Dowsing Offshore Wind Farm ........................................................10 3.2.1 Site Description ...........................................................................................10 3.2.2 Sediment Properties.....................................................................................10 3.2.3 Hydrodynamic Properties ..............................................................................11 3.2.4 Monitoring ..................................................................................................11 3.3 Discussion and Conclusions ................................................................................16 4. Review of Seabed Morphology ...........................................................................17 4.1 Background......................................................................................................17 4.2 Burbo Bank Offshore Wind Farm..........................................................................17 4.2.1 Site Description ...........................................................................................17 4.2.2 Monitoring ..................................................................................................18 4.3 Thornton Bank Offshore Wind Farm .....................................................................20 4.3.1 Site Description ...........................................................................................20 4.3.2 Monitoring ..................................................................................................20 4.4 Discussion and Conclusions ................................................................................21 5. Review of Scour .................................................................................................22 5.1 Background......................................................................................................22 5.2 Robin Rigg Offshore Wind Farm...........................................................................23 5.2.1 Site Description ...........................................................................................23 5.2.2 Sediment Properties.....................................................................................23 5.2.3 Hydrodynamic Properties ..............................................................................24 5.2.4 Monitoring ..................................................................................................25 5.3 Princess Amalia (Q7) Offshore Wind Farm.............................................................29 5.3.1 Site Description ...........................................................................................29 5.3.2 Sediment Properties.....................................................................................30 5.3.3 Hydrodynamic Properties ..............................................................................31 i A Further Review of Sediment Monitoring Data 5.3.4 Monitoring ..................................................................................................31 5.4 Barrow Offshore Wind Farm................................................................................32 5.4.1 Site Description ...........................................................................................32 5.4.2 Sediment Properties.....................................................................................33 5.4.3 Hydrodynamic Properties ..............................................................................33 5.4.4 Monitoring ..................................................................................................33 5.5 Kentish Flats Offshore Wind Farm ........................................................................34 5.5.1 Site Description ...........................................................................................34 5.5.2 Sediment Properties.....................................................................................35 5.5.3 Hydrodynamic Properties ..............................................................................35 5.5.4 Monitoring ..................................................................................................35 5.6 North Hoyle Offshore Wind Farm .........................................................................36 5.6.1 Site Description ...........................................................................................36 5.6.2 Sediment Properties.....................................................................................36 5.6.3 Hydrodynamic Properties ..............................................................................37 5.6.4 Monitoring ..................................................................................................38 5.7 Discussion and Conclusions ................................................................................39 6. Lessons Learnt ...................................................................................................42 6.1 Data Management .............................................................................................42 6.2 Evidence Base ..................................................................................................42 6.3 Suspended Sediment Concentrations ...................................................................42 6.4 Morphology ......................................................................................................42 6.5 Scour ..............................................................................................................43 7. Recommendations..............................................................................................44 7.1 Suspended Sediment Concentrations ...................................................................44 7.2 Morphology ......................................................................................................44 7.3 Scour ..............................................................................................................45 Figures .......................................................................................................................49