Cell 11 Regional Monitoring Strategy (CERMS) 2010 Monitoring Update Report
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Cell 11 Regional Monitoring Strategy (CERMS) 2010 Monitoring Update Report Cell 11 Regional Monitoring Strategy (CERMS) 2010 Monitoring Update Report Cell 11 Regional Monitoring Strategy (CERMS) 2010 Monitoring Update Report Contents Amendment Record This report has been issued and amended as follows: Issue Revision Description Date Approved by 2010 update to CERMS baseline report. Updated by Lily Booth. Comments and 1 1 28.2.12 Nigel Pontee further updates from Alan Wiliams and Ken Pye. 2010 update to Cerms baseline report. 1 1.1 Updated by P.Wisse, Smbc following 31.10.12 comments in first draft Halcrow Group Limited Burderop Park, Swindon, Wiltshire SN4 0QD Tel +44 (0)1793 812479 Fax +44 (0)1793 812089 www.halcrow.com Halcrow Group Limited has prepared this report in accordance with the instructions of their client, Sefton Council, for their sole and specific use. Any other persons who use any information contained herein do so at their own risk. © Halcrow Group Limited 2014 Metadata Addressee Aggregation Audience Coastal/Environmental Engineers Contributor(s) Coverage Cell 11: Great Orme’s Head to the Scottish Border (including sub-cells 11a, b, c, d and e) Creator Halcrow Group Ltd Date Description Cell 11 Regional Monitoring Strategy (CERMS) 2010 Monitoring Update Report Format Text Identifier Language English Location Mandate CERMS Regional Monitoring Framework Publisher Sefton Council Relation Status Draft Subject Coastal Processes Title CERMS 2010 Monitoring Update Report Type Text/report Table of Contents LIST OF TABLES .................................................................................................................................... II LIST OF FIGURES .................................................................................................................................. III EXECUTIVE SUMMARY ......................................................................................................................... 1 1 INTRODUCTION ............................................................................................................................ 2 1.1 CERMS OBJECTIVES 2 1.2 THE ROLE OF THIS REPORT 2 1.3 RELATED STUDIES 3 2 DATA AVAILABILITY .................................................................................................................... 5 2.1 INTRODUCTION 5 2.2 LOCAL FRAMEWORK DATA 5 2.3 CERMS STRATEGIC MONITORING 7 2.4 SUMMARY OF DATA HELD IN EXISTING SANDS DATABASE 8 2.5 OTHER LOCAL DATA COLLECTED BUT NOT CURRENTLY RECORDED IN SANDS 24 2.6 OTHER MONITORING PROGRAMMES 25 2.7 DATA / INFORMATION AVAILABLE FROM LINKED STUDIES 27 2.8 OTHER THIRD PARTY DATA SOURCES 33 3 CELL WIDE BASELINE ................................................................................................................ 34 3.1 INTRODUCTION 34 3.2 EXISTING UNDERSTANDING 34 3.3 ISSUES AND UNCERTAINTIES 56 4 SUB-CELL BASELINES ................................................................................................................. 62 4.1 INTRODUCTION 62 4.2 SUB CELL 11A 63 4.3 SUB-CELL 11B 88 4.4 SUB CELL 11 C 105 4.5 SUB CELL 11 D 131 4.6 SUB CELL 11 E 146 5 OPERATIONAL MATTERS ........................................................................................................ 164 5.1 DATA COLLATION AND MANAGEMENT 164 CONCLUSIONS FROM CERMS REVIEW 165 6 CONCLUSION ............................................................................................................................. 167 7 RECOMMENDATIONS ............................................................................................................... 171 8 REFERENCES ............................................................................................................................... 188 APPENDIX A i List of Tables Table 2.1 Sub-cell 11a fixed monitoring instruments…………………………………………... 10 Table 2.2 Sub-cell 11b fixed monitoring instruments…………………………………………... 15 Table 2.3 Sub-cell 11c fixed monitoring instruments…………………………………………... 18 Table 2.4 Sub-cell 11e fixed monitoring instruments…………………………………………... 22 Table 3.1 Uncertainties in present regional understanding…………………………………….. 40 Table 3.2 Recommendations for CERMS arising from CETaSS Study 43 Table 4.1 Extreme Sea Levels for North Wales (Atkins (2008) North Wales Tidal Flood Mapping Phase II Report)……………………………………………………………. 63 Table 4.2 Extreme Sea Levels for Central North West England (JBA Consulting (2007), Central Area Tidal Areas Benefiting from Defence. Final Sea Level Report).............. 64 Table 4.3 Sub-Cell 11a - Supporting information for Conceptual Understanding.......................... 68 Table 4.4 Extreme Sea Levels for Central North West England (JBA Consulting (2007), Central Area Tidal Areas Benefiting from Defence. Final Sea Level Report).............. 90 Table 4.5 Sub-Cell 11b - Supporting information for Conceptual Understanding......................... 93 Table 4.6 Extreme Sea Levels for Central North West England (JBA Consulting (2007), Central Area Tidal Areas Benefiting from Defence. Final Sea Level Report).............. 109 Table 4.7 Extreme Sea Levels for North Area, North West England (JBA Consulting (2007), North Area Tidal Areas Benefiting from Defence. Final Sea Level Report)................. Table 4.8 Sub-Cell 11c - Supporting information for Conceptual Understanding.......................... 113 Table 4.9 Extreme Sea Levels for North Area, North West England (JBA Consulting (2007), North Area Tidal Areas Benefiting from Defence. Final Sea Level Report)................. 137 Table 4.10 Sub-Cell 11d - Supporting information for Conceptual Understanding........................ 140 Table 4.11 Extreme Sea Levels for North Area, North West England (JBA Consulting (2007), North Area Tidal Areas Benefiting from Defence. Final Sea Level Report)................. 153 Table 4.12 Sub-Cell 11e - Supporting information for Conceptual Understanding......................... 154 ii List of Figures Figure 2.1 Overview of data currently held in SANDS, database Sub-cell 11a………………... 14 Figure 2.2 Overview of data currently held in SANDS, database Sub-cell 11b……………….... 16 Figure 2.3 Overview of data currently held in SANDS, database Sub-cell 11c ……………….. 19 Figure 2.4 Overview of data currently held in SANDS, database Sub-cell 11d………………... 21 Figure 2.5 Overview of data currently held in SANDS, database Sub-cell 11e………………… 23 Figure 3.1 Overview of Cell 11 study area, showing SMP2 sub-cell frontages………………… 31 Figure 3.2 Bathymetry used in Halcrow’s Irish Sea Regional Model………….. 32 Figure 3.3 Wind rose offshore from Barrow………………………………………...……….... 33 Figure 3.4 Peak depth averaged flood currents in Cell 11………………………………….... 35 Figure 3.5 Peak depth averaged ebb currents in Cell 11……………………………………….. 36 Figure 3.6 Residual (monthly average tidal currents)……………………………………….... 38 Figure 3.7 Wave roses for the Cell 11 coastline (adapted from Halcrow 2002)……………. 42 Figure 3.8 Distribution of sea-bed sediments. Classification after Folk (1954). Modified from Jackson et. al., (1995)……………………………………………………………… 44 Figure 3.9 Mean sea bed bottom stress. After Pingree and Griffiths (1979)…………………... 45 Figure 3.10 Preliminary schematic representation of the principal marine and fluvial sediment transport pathways in the eastern Irish Sea (Pye and Blott, 2009)…………………. 46 Figure 4.1 Location map of sub-cell 11a…………………………………………………….... 61 Figure 4.2 Sub-cell 11a Conceptual Understanding…………………………………………….. 67 Figure 4.3 Location map of sub-cell 11b………………………………………………………... 88 Figure 4.4 Sub-cell 11b Conceptual Understanding………………………………………….. 92 Figure 4.5 Location map of sub-cell 11c…………………………………………………….... 106 Figure 4.6 Sub-cell 11c Conceptual Understanding…………………………………………….. 112 Figure 4.7 Location map for sub-cell 11d…………………………………………………….. 135 Figure 4.8 Sub-cell 11d Conceptual Understanding………………………………………….. 139 Figure 4.9 Location map for sub-cell 11e…………………………………………………………... 151 Figure 4.10 Sub-cell 11e Conceptual Understanding…………………………………………… 156 iii Glossary Term Definition Accretion In geography, accretion means the land increasing due to sediment being added to it. Dune system Dunes are subject to dune processes, i.e. accretion (via the onshore transport of sand), and erosion, which maintain the same structure and habitat. Aeolian transport Sediment transport by wind Alluvial deposits loose, unconsolidated (not cemented together into a solid rock), soil or sediments, eroded, deposited, and reshaped by water in some form in a non- marine setting Anthropogenic General term used to describe the influence of man e.g. the influence of sea influences/modification defences or management actions on coastal processes. Barometric pressure Atmospheric pressure. Barrier The function of a barrier is to control the water level. It consists of a combination of a concrete or a steel structure with or without adjacent rockfill dams. Bathymetry The measurement of depths of water in oceans, seas and lakes; also the information derived from such measurements. Beach A deposit of non-cohesive material (e.g. sand, gravel) situated on the interface between dry land and the sea (or other large expanse of water) and actively "worked" by present-day hydrodynamic processes (i.e. waves, tides and currents) and sometimes by winds Beach profile A cross-section taken perpendicular to a given beach contour; the profile may include the face of a dune or seawall, extend over the backshore, across the foreshore, and seaward underwater into the nearshore zone. Beach Recharge This