Level 1 Strategic Flood Risk Assessment
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Level 1 Strategic Flood Risk Assessment Epping Forest District Council Harlow Council March 2010 1 Strategic Flood Risk Assessment Final Report Issue Date: xxx Prepared by: Ben Meuli Checked by: xxx (EFDC), xxx (Harlow) Approved by: xxx (EFDC), xxx (Harlow) Version History Version xx.xx Revised xx.xx.xx 2 CONTENTS 1. INTRODUCTION................................................................................................5 1.1 OVERVIEW .....................................................................................................................5 1.2 AIMS AND OBJECTIVES ....................................................................................................5 1.3 THE SEQUENTIAL AND EXCEPTION TESTS....................................................................6 2. FLOOD RISK IN EPPING FOREST AND HARLOW DISTRICTS.......................8 2.1 STUDY AREA ..................................................................................................................8 2.1.1 Epping Forest..................................................................................................................8 2.1.2 Harlow..............................................................................................................................9 2.2. GEOGRAPHY, GEOLOGY AND RIVER CATCHMENTS.............................................................9 2.2.1 Epping Forest ...................................................................................................................9 2.2.2 Harlow............................................................................................................................10 2.3 HISTORY OF FLOODING .................................................................................................11 2.3.1 Epping Forest .................................................................................................................11 2.3.2 Harlow............................................................................................................................12 3. POLICY FRAMEWORK....................................................................................13 3.1 OVERVIEW ...................................................................................................................13 3.2 OBJECTIVE ..................................................................................................................13 3.3 THE EUROPEAN POLICY FRAMEWORK ............................................................................13 3.3.1 The Water Framework Directive 2000..........................................................................13 3.3.2 The Habitats Directive 1992..........................................................................................13 3.4 NATIONAL POLICY AND LEGISLATION IN ENGLAND ............................................................13 3.4.1 The Planning and Compulsory Purchase Act 2004.......................................................13 3.4.2 Future Water 2007.........................................................................................................14 3.4.3 The Town and Country Planning (Flooding) (England) Direction 2007......................14 3.4.4 The Town and Country Planning (General Permitted Development)(Amendment) (No. 2) England) Order 2008 Guidance on the Permeable Surfacing of Front Gardens – 10 September 2008......................................................................................................................14 3.4.5 Surface Water Management Plan (SWMP) Technical Guidance – Living draft version 1 (February 2009)...................................................................................................................14 3.4.6 The Flood Risk Regulations 2009..................................................................................15 3.4.7 The Flood and Water Management Act (2010).............................................................15 3.4.8 Planning policy statements............................................................................................16 3.4.9 Planning Policy Statement 1: Delivering Sustainable Development (PPS1) and PPS: Planning and Climate Change – Supplement to PPS1 (2007) and Planning Policy Statement Consultation: Planning for a Low Carbon Future in a Changing Climate (March 2010)....16 3.4.10 Planning Policy Statement 3: Housing (PPS3) (2007).................................................16 3.4.11 Planning Policy Statement 25: Development and Flood Risk (PPS 25) (2010) Planning Policy Statement 25: Development and Flood Risk - Practice Guide – Published 7 December 2009........................................................................................................................................16 3.5 REGIONAL PLANNING POLICY ........................................................................................17 3.5.1 Thames Catchment Flood Management Plan – Managing flood risk (2009)...............17 3.5.2 Rye Meads Water Cycle Strategy..................................................................................17 3.6 LOCAL PLANNING POLICY..............................................................................................17 3.6.1 EFDC Local Plan (1998)................................................................................................17 3.6.2 Replacement Harlow Local Plan (2006) .........................................................................19 4. STRATEGIC FLOOD RISK ASSESSMENT.....................................................21 4.1 OVERVIEW...................................................................................................................21 4.2 LIST OF MAPS ..............................................................................................................21 4.3 LIST OF DATA SOURCES ................................................................................................21 4.4 FLUVIAL FLOODING.......................................................................................................22 4.5 SURFACE WATER FLOODING ..........................................................................................26 4.6 GROUNDWATER FLOODING............................................................................................26 4.7 SEWER FLOODING ........................................................................................................27 3 4.8 FLOOD INFRASTRUCTURE AND ARTIFICIAL SOURCES OF FLOODING ....................................27 4.8.1 Epping Forest District.....................................................................................................28 4.8.2 Harlow............................................................................................................................30 4.9 RESIDUAL RISK ............................................................................................................30 4.10 CLIMATE CHANGE.......................................................................................................31 5. EMERGENCY PLANNING...............................................................................32 5.1 CRITICAL INFRASTRUCTURE ..........................................................................................32 5.2 FLOOD WARNING..........................................................................................................32 6. DEVELOPMENT GUIDANCE...........................................................................34 6.1 REQUIREMENTS FOR SITE SPECIFIC FLOOD RISK ASSESSMENT .........................................34 6.2 DEVELOPMENT WITHIN EPPING FOREST DISTRICT AND EFDC FLOOD RISK ASSESSMENT ZONES 35 6.3 SUDS – SUSTAINABLE DRAINAGE SYSTEMS...................................................................36 7. RECOMMENDATIONS.....................................................................................38 7.1 CLIMATE CHANGE.........................................................................................................38 7.2 FUNCTIONAL FLOODPLAIN/FLOOD ALLEVIATION AND STORAGE SCHEMES .............................38 7.3 OTHER FORMS OF FLOODING .........................................................................................38 7.4 SITE ALLOCATIONS .......................................................................................................38 7.5 DEVELOPMENT PROPOSALS...........................................................................................39 7.6 EMERGENCY PLANNING/RISK AWARENESS .......................................................................39 8. ABBREVIATIONS AND GLOSSARY...............................................................41 9. REFERENCES.................................................................................................45 10. APPENDICES...................................................................................................46 List of Figures and Tables FIGURE 1 STUDY AREA 8 TABLE 1 SFRA DATA SOURCES 19 TABLE 2 FLOOD ZONE DEFINITIONS FROM PPS25 20 TABLE 3 FLOOD ZONE 3B DATA SOURCES 21 TABLE 4 FLOOD ZONE 3A DATA SOURCES 22 TABLE 5 FLOOD ZONE 2 DATA SOURCES 22 TABLE 6 CLIMATE CHANGE FLOOD ZONE 3A DATA SOURCES 23 TABLE 7 CLIMATE CHANGE FLOOD ZONE 3B DATA SOURCES 23 TABLE 8 EMERGENCY PLANNING INFRASTRUCTURE 30 TABLE 9 COMMON SUDS METHODS 35 List of maps Map 1 Watercourses, ponds, lakes, Main Rivers Map 2 Main River catchments Map 3 Historical flooding incidents Map 4 Flood Zones Map 5 Climate change Map 6 Areas susceptible to surface water flooding Map