Amber Valley Strategic Flood Risk Assessment Level 1 Report (Vol. I) Amber Valley Borough Council June 2009 Faber Maunsell Amber Valley Strategic Flood Risk Assessment i Table of Contents Table of Contents ......................................................................................................................... i Executive Summary .................................................................................................................... v 1 Introduction ..................................................................................................................... 1 2 Planning Policy and Flood Risk..................................................................................... 3 Planning Policy Statement 25 (PPS25) ............................................................................ 3 Site-Specific Flood Risk Assessments (FRA) ................................................................... 8 The East Midlands Regional Spatial Strategy and Regional Plan .................................. 10 River Trent Catchment Flood Management Plan............................................................ 12 3 Methodology .................................................................................................................. 15 General ............................................................................................................................ 15 Strategic Flood Risk Maps .............................................................................................. 15 Flood Zone Outlines ........................................................................................................ 16 Climate Change .............................................................................................................. 18 Flood Defences and Reservoir Safety ............................................................................ 18 Sustainable Drainage Systems (SuDS) .......................................................................... 18 4 Data Collection .............................................................................................................. 25 Schedule of Data and Information .................................................................................. 25 Limitations of Data Gathered .......................................................................................... 28 5 Area Overview ............................................................................................................... 29 6 Flooding Sources .......................................................................................................... 33 Flooding from Rivers and Streams ................................................................................. 33 Surface Water Sewers .................................................................................................... 34 Artificial Sources (Reservoirs, Runoff Retention Ponds and Canals) ............................. 35 Groundwater.................................................................................................................... 35 Overland Flow ................................................................................................................. 36 Effects of Climate Change .............................................................................................. 36 7 Flooding History ............................................................................................................ 39 8 Flood Emergency Plans ............................................................................................... 41 9 Overview of Flood Risk in Urban Areas ...................................................................... 43 Alfreton ............................................................................................................................ 44 Belper.. ............................................................................................................................ 44 Heanor. ......................................................................................................................... …45 Ripley… ........................................................................................................................... 45 10 User Guide ..................................................................................................................... 47 The Sequential Approach ................................................................................................ 47 The Sequential Test ........................................................................................................ 48 The Exception Test ......................................................................................................... 53 Optimising the Use of the SFRA ..................................................................................... 54 Flood Risk Management Policies for the Local Development Framework ..................... 56 Guidance for Developers ................................................................................................ 58 Sustainable Drainage Systems (SuDS) .......................................................................... 59 Continued over ….. Faber Maunsell Amber Valley Strategic Flood Risk Assessment ii Continued …. 11 Conclusions ................................................................................................................... 63 12 Recommendations ........................................................................................................ 65 Glossary ..................................................................................................................................... 67 References ................................................................................................................................. 71 Index of Figures Figure 1- 1: Extent of Amber Valley Borough .......................................................................... 1 Figure 10- 1: Application of the Sequential Test at Local Level for LDD Preparation .............. 49 Figure 10- 2: Application of the Exception Test ....................................................................... 53 Index of Tables Table 2- 1: Flood Zones – Risk and Probability ...................................................................... 3 Table 2- 2: Scope of Site Specific Flood Risk Assessment .................................................... 9 Table 2- 3: Future Housing Provision in the East Midlands .................................................. 10 Table 2- 4: Future Housing Provision in the Three Cities Sub-Area ..................................... 11 Table 2- 5: CFMP Flood Risk Management Policies ............................................................ 12 Table 2- 6: Selected Policies for Amber Valley Borough ...................................................... 13 Table 3- 1: Local Amendments to Flood Zone Envelopes .................................................... 17 Table 3- 2: GIS Tables Used for Mapping ............................................................................ 19 Table 3- 3: Summary of Maps Created ................................................................................. 23 Table 4- 1: Schedule of data and information for the preparation of the SFRA .................... 25 Table 5- 1: Significant Water Management Structures (from NFCDD data) ......................... 30 Table 5- 2: Significant Water Management Structures (from OS maps and site visit) ......... 31 Table 7- 1: Details of Historical Flooding Information ........................................................... 39 Table 10- 1: Strategic Flood Risk Assessment and the Planning Process ............................ 55 Table 10- 2: Selection of appropriate guidance notes from the Environment Agency’s Flood Risk Standing Advice [16] .................................................................................. 57 Table 10- 3: Typical Infiltration Coefficients based on Soil Texture ....................................... 60 Index of Maps Figure 001: River Network Figure 002: Strategic Flood Risk Map Figure 003: Water Management Infrastructure Figure 004: Flooding History Figure 005: Potential Flood Risk Figure 006: Existing Emergency Plans Note: All maps are contained in Voume II of this Report.) Continued over ….. Faber Maunsell Amber Valley Strategic Flood Risk Assessment iii Continued …. Index of Appendices Appendix A - Document Management Guide Appendix B - Flooding History Appendix C - CFMP Recommendations Appendix D - Reservoir Information Appendix E - Groundwater Source Protection Zones Appendix F - Recommended Flood Risk Policy and Guidance Statements Appendix G - Water Management Infrastructure Appendix H - Inception Report Faber Maunsell Amber Valley Strategic Flood Risk Assessment iv - This page left blank intentionally - Faber Maunsell Amber Valley Strategic Flood Risk Assessment v Executive Summary Faber Maunsell Limited was appointed by Amber Valley Borough Council (AVBC) in February 2008 to undertake a Level 1 Strategic Flood Risk Assessment (SFRA) of Amber Valley Borough, the scope of which was described in a Brief issued by the Borough Council [1]. The agreed methodology, designed to comply with Planning Policy Statement 25 (PPS25) [2] and its Practice Guide [3], divides the study into two phases. The first phase of the study consisted of the collection and evaluation of all available data and information relevant to