Charnwood Strategic Flood Risk Assessment Update
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Charnwood Strategic Flood Risk Assessment Update Final Report June 2014 This page is intentionally left blank Charnwood Borough Council Project Manager Liz Aspray Charnwood Borough Council Southfield Road Loughborough Leicestershire LE11 2TN JBA Project Manager Claire Gardner The Library St Philip‟s Courtyard Church End COLESHILL B46 3AD Revision History Revision Ref / Amendments Issued to Date Issued Liz Aspray (Charnwood Borough Council) Tim Andrews Draft (version 1) (Environment Agency) February 2014 Greg Cunningham (Leicestershire County Council) Amendments based on Charnwood Borough Council, Leicestershire Liz Aspray (Charnwood County Council and Environment Borough Council) Final Draft Agency comments. Tim Andrews (version 1) Additional section added to include (Environment Agency) April 2014 assessment of all available sites Greg Cunningham within Charnwood Borough to (Leicestershire County provide support for the Sequential Council) test. Liz Aspray (Charnwood Amendments based on Charnwood Borough Council) Borough Council, Leicestershire Tim Andrews Final (version 1) County Council and Environment (Environment Agency) June 2014 Agency comments. Greg Cunningham (Leicestershire County Council) Contract This report describes work commissioned by Charnwood Borough Council by a letter dated 19 September 2013. Charnwood Borough Council‟s representative for the contract was Liz Aspray. Andrew Waite and Claire Gardner of JBA Consulting carried out this work. Prepared by .................................................. Andrew Waite BSc MRes Assistant Analyst Claire Gardner BSc MSc FRGS Analyst Reviewed by ................................................. David Kearney BSc MSc MCIWEM C.WEM Principal Analyst Purpose This document has been prepared as a draft report for Charnwood Borough Council. JBA Consulting accepts no responsibility or liability for any use that is made of this document other than by the Client for the purposes for which it was originally commissioned and prepared. JBA Consulting has no liability regarding the use of this report except to Charnwood Borough Council. Copyright © Jeremy Benn Associates Limited 2014 Carbon Footprint A printed copy of the main text in this document will result in a carbon footprint of 643g if 100% post-consumer recycled paper is used and 819g if primary-source paper is used. These figures assume the report is printed in black and white on A4 paper and in duplex. JBA is aiming to reduce its per capita carbon emissions. Acknowledgements We would like to acknowledge the assistance of Liz Apray (Charnwood Borough Council), Tim Andrews (Environment Agency) and Jonathan McGuiness and Greg Cunningham (Leicestershire County Council) for their support and assistance with this study. Front cover image: Meadow Lane, Loughborough Meadows, during the 2012 floods This page is intentionally left blank Executive summary Introduction This Charnwood Borough Council Strategic Flood Risk Assessment (SFRA) 2014 Update report updates the document “Charnwood Borough Council: Charnwood Strategic Flood Risk Assessment Final Report, April 2008”. This report has been prepared to update the work that was included in the previous SFRA and provide appropriate supporting evidence for the Charnwood Borough Plan. Since the previous SFRA there have been a number of changes to the planning system, including the Localism Act (2011) and the 2012 National Planning Policy Framework (NPPF) with accompanying Planning Practice Guidance (March 2014). In addition, the provisions of the Flood and Water Management Act (2010) have been substantially commenced under a programme that was initiated by Defra in April 2010 and the Flood Risk Regulations came into force in December 2009 (these regulations transposed the EU „Floods Directive‟ into UK law). The purpose of this SFRA update is to provide information on the changes to planning, policy and guidance since the previous SFRA; provide a detailed assessment of the flood hazard within the Flood Zones; provide information on existing defences and flood risk management measures; allow a sequential approach to site allocation to be undertaken within a flood zone; and allow development of the policies and practices required to ensure that development in Flood Zones 2 and 3 satisfies the requirements of the Exception Test. SFRA objectives There are two levels of SFRAs 1. Level One: where flooding is not a major issue and where development pressures are low. The Assessment should be sufficiently detailed to allow application of the Sequential Test 2. Level Two: where land outside flood risk areas cannot appropriately accommodate all the necessary development and the NPPF‟s Exception Test needs to be applied. The Assessment should consider the detailed nature of the flood characteristics within a flood zone. A Level 1 SFRA was completed in April 2008, comprising of a desk-based study using existing information to allow application of the Sequential Test and identify whether application of the Exception Test is likely to be necessary. The objectives of this SFRA update are a hybrid approach involving a general update and review of the 2008 SFRA, which covers the whole of the Borough (level 1) and a more detailed assessment of allocations included in the emerging draft Core Strategy. SFRA outputs Level one outputs Maps showing the local planning authority area, Main Rivers, ordinary watercourses, and flood zones An assessment of the implications of climate change for flood risk at allocated development sites Areas at risk from other sources of flooding, for example surface water or reservoir Flood risk management measures, including location and standard of flood defences, flood warning coverage and emergency plans Recommendations about the identification of critical drainage areas and the potential need for surface water management plans 2013s7588 Charnwood BC SFRA Update Final Draft v1.0 i Advice on the likely applicability of sustainable drainage systems for managing surface water runoff at key development sites Advice of the preparation of flood risk assessments for development sites Level two outputs An appraisal of current condition of flood defence infrastructure An appraisal of the probability and consequences of overtopping or failure of flood risk management infrastructure, including an allowance for climate change Definition and mapping of the function floodplain Definition and mapping of o Flood depth o Flood velocity o Flood hazard Maps showing the distribution of flood risk across all flood zones from all sources of flooding Advice on appropriate policies for sites which could satisfy the first part of the Exception Test and on the requirements that would be necessary for a site-specific flood risk assessment supporting a planning application for an application to pass the second part of the Exception Test Advice on the preparation of site-specific flood risk assessments for sites of varying risk across the flood zones, including information about the use of sustainable drainage techniques Recommendations to inform policy, development control and technical issues Summary The Charnwood SFRA update has considered all sources of flooding, including fluvial, pluvial, groundwater, canal, reservoir and sewer flooding, within the Charnwood Borough. An assessment of the flood defences in the Borough has been undertaken, including defence condition and standard and the residual risk. Flood risk has been assessed for all development options which have been considered for inclusion in the draft Core Strategy. Flood risk has been assessed in detail for the development options being taken forward in the Core Strategy. Guidance for the requirements for a site specific Flood Risk Assessment for these sites is provided (section 7.2), as well as general guidance on flood risk assessment for any development proposals within the Charnwood Borough. The updated Flood Map for Surface Water is provided, indicating the likelihood of surface water flooding in the Charnwood Borough. Surface water flooding is a risk in many of the areas. Advice has been provided regarding suitable SuDS options. A broad scale assessment of Critical Drainage Areas has been undertaken. Green Infrastructure within the Borough has been assessed and the WFD status of the Borough‟s watercourses assessed. Recommendations Key recommendations It is recommended that the mapping produced for this SFRA update is used in preference to the previous SFRA published in 2008. It is recommended that developers refer to the FRA recommendations provided in the proposed development site summary tables in Section 7.2 as well as the general guidance on flood risk assessment in Section 12. The key requirements for future development are summarised below: 2013s7588 Charnwood BC SFRA Update Final Draft v1.0 ii o All sites within Zones 2 and 3 will require a detailed Flood Risk Assessment in accordance with NPPF, making reference to Sections 7.2 and 12, and associated maps of this report. Consultation with Charnwood Borough Council, Leicestershire County Council and the Environment Agency is strongly recommended at an early stage in the FRA process. o The layout of buildings and access routes should adopt a sequential approach, steering buildings (and hence people) towards areas of lowest risk within the boundaries of the site. This will also ensure that the risk of flooding is not worsened by, for example, blocked flood flow routes. o The FRA requirements defined in Section 12 of this Level