Kettering Borough Surface Water Management Plan Kettering Borough Council October 2018 Final Report October 2018 AECOM Kettering Borough Surface Water Management Plan i Quality information Prepared by Checked by Approved by Craig Boorman James Latham Sarah Kelly Assistant Consultant Senior Flood Risk Engineer Regional Director Sarah Littlewood Sarah Kelly Senior Consultant Regional Director James Latham Senior Consultant Revision Revision date Details Authorised Name Position 1 October 2016 Draft SWMP Report Oct. 2016 JR Director - Water for Client Comment 2 May 2017 Final Draft SWMP May 2017 JR Director - Water Report incorporating stakeholder comments 3 March 2018 Final Draft SWMP March 2018 SK Regional Director Report incorporating stakeholder comments 4 October 2018 Final Report October 2018 SK Regional Director Prepared for Kettering Borough Council AECOM Infrastructure & Environment UK Limited Midpoint Alencon Link Basingstoke Hampshire RG21 7PP UK T: +44(0)1256 310200 aecom.com © 2018 AECOM Infrastructure & Environment UK Limited. 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Final Report October 2018 AECOM Kettering Borough Surface Water Management Plan ii Table of Contents Quality information .......................................................................................................................................................................................... i Table of Contents ............................................................................................................................................................................................ ii Executive Summary ................................................................................................................................................................................. ES-1 1 Introduction ............................................................................................................................................................................................. 1-1 1.1 Background ................................................................................................................................................................................................ 1-1 1.2 What is a Surface Water Management Plan ................................................................................................................................... 1-1 1.3 Surface Water Management Plan Process ..................................................................................................................................... 1-1 1.4 Objectives................................................................................................................................................................................................... 1-3 1.5 Linking and Integrating Surface Water Management ................................................................................................................. 1-3 2 Phase I Preparation ............................................................................................................................................................................... 2-1 2.1 Introduction................................................................................................................................................................................................ 2-1 2.2 Identify the need for a Surface Water Management Plan ......................................................................................................... 2-1 2.3 Establish Flood Risk Partnership ........................................................................................................................................................ 2-1 2.4 Clarifying the Scope of the Surface Water Management Plan ................................................................................................ 2-3 2.5 Chosen Level of Assessment for the Kettering Borough Surface Water Management Plan ...................................... 2-6 3 Phase II Risk Assessment ................................................................................................................................................................... 3-1 3.1 Strategic Risk Assessment .................................................................................................................................................................. 3-1 3.2 Intermediate Risk Assessment ........................................................................................................................................................ 3-12 3.3 Detailed Risk Assessment ................................................................................................................................................................. 3-25 3.4 Phase II (Risk Assessment) Recommendations ......................................................................................................................... 3-44 4 Phase III Options .................................................................................................................................................................................... 4-1 4.1 Overview ..................................................................................................................................................................................................... 4-1 4.2 Assessment Methodology ................................................................................................................................................................... 4-1 4.3 Borough Wide Flood Management Option Appraisal ................................................................................................................. 4-8 4.4 Options Appraisal for CDC 1 Kettering Town ............................................................................................................................. 4-27 4.5 Options Appraisal for CDC 6 East Brook ...................................................................................................................................... 4-36 4.6 Options Appraisal for CDC 2 Desborough .................................................................................................................................. 4-51 5 Phase IV Implementation & Review ................................................................................................................................................. 5-1 5.1 Action Plan ................................................................................................................................................................................................. 5-1 5.2 Recommendations and Actions ......................................................................................................................................................... 5-1 5.3 Implementation ......................................................................................................................................................................................... 5-9 5.4 Review and Ongoing Monitoring ..................................................................................................................................................... 5-13 List of Appendices Appendix A. Mapping Appendix B. Historic Flood Incidents Appendix C. Phase II CDC Prioritisation Appendix D. Model Build Report Appendix E. High-level Options Assessments Appendix F. Action Plan Final Report October 2018 AECOM Kettering Borough Surface Water Management Plan iii List of Tables Table 1 – Summary of SWMP ‘Intermediate’ Risk Assessment .......................................................................................................... ES-2 Table 2 – Summary of SWMP ‘Detailed’ Risk Assessment ................................................................................................................... ES-3 Table 3 – Summary of SWMP Borough Wide Flood Management Measures ................................................................................ ES-4 Table 4 – Summary of detailed options assessment .............................................................................................................................. ES-6 Table 1-1 – Kettering Housing Distribution (Source: North Northamptonshire JCS Adopted, July 2016) ............................ 1-3 Table 2-1 – Flood Risk Partners for Kettering Borough SWMP .............................................................................................................. 2-2 Table 2-2 – Main SWMP data sources and use ............................................................................................................................................ 2-3 Table 2-3 – Levels of Assessment in a SWMP Study (adapted from Defra SWMP Technical Guidance, March 2010) ..... 2-6 Table 3-1 – Settlement Prioritisation ...........................................................................................................................................................