North Lincolnshire Council Local Flood Risk Management Strategy August 2016 Amec Foster Wheeler Environment & Infrastructure UK Limited & North Lincolnshire Council August 2016 Page | i Executive summary Flooding is a natural phenomenon, the consequences of which can be exacerbated by poor management of the environment. The risk of flooding is expected to increase in future due to the effects of climate change, particularly if flooding is not sufficiently planned for when undertaking new developments. Whilst it is not possible to prevent all instances of flooding, it is possible to take actions to manage these risks and to reduce the impacts on communities, both now and in the future. Purpose of this report As the Lead Local Flood Authority, North Lincolnshire Council are responsible for managing flood risk from ‘local’ sources. This report is North Lincolnshire Council’s Local Flood Risk Strategy (LFRMS) Summary for Public Consultation. It presents the summary of North Lincolnshire’s preferred strategy for managing ‘local’ flood risks in the district, i.e. flooding arising from: surface run-off; groundwater; and Ordinary Watercourses (generally small rivers and streams). How this Strategy fits into the wider management of flood risk from non-local sources? Much of North Lincolnshire is flat and low lying and is therefore susceptible to flooding from a range of sources. Therefore, whilst this document focuses on local flood risks, it also sets out how all of the Risk Management Authorities covering North Lincolnshire have agreed to work together to consider risks from all potential sources of flooding. The Environment Agency are currently developing a Flood Risk Management Plan for the Humber catchment, within which North Lincolnshire is located, which will consider flooding from non-local sources, such as rivers and the sea. Together, the Humber Flood Risk Management Plan and this LFRMS will ensure that flooding from local sources is appropriately quantified alongside flood risk from these non-local sources, under the responsibility of the risk management authorities. Who is this ‘local’ Strategy for? This LFRMS has been developed in conjunction with the Risk Management Authorities present in North Lincolnshire, including the Environment Agency, Internal Drainage Boards and Water Companies. It sets out the roles and responsibilities of all of the Risk Management Partners and provides the necessary framework for fostering partnerships between these Flood Risk Management Partners, particularly in delivering flood risk management schemes. Ultimately, however, this strategy is for the residents and businesses of North Lincolnshire, set out how the Council intends to manage local flood risks, as well as contribute to management from non-local sources, and to engage and inform our residents on their own responsibilities, and enable them to contribute to the management of flood risk. How do we propose to manage local flood risk In developing a business case for new flood protection works, cost and benefits to property and infrastructure can only be considered once. It is important, therefore, that all risks are adequately identified in planning and delivering flood defence schemes. By working together with our flood risk management partners, we can achieve this. This strategy documents how we will work with our partners to deliver this objective in line with other plans and strategies, for example the Environment Agency’s strategy for the Isle of Axholme and the Humber Flood Risk Management Plan. Since 2007, North Lincolnshire Council has collected much information on historic local sources flood events, and we have mapped and recorded areas of drainage infrastructure in many settlement areas. We will continue to build upon the information gathered to date, with the intention of completing a comprehensive asset database for the whole council area. By combining our local knowledge of areas that have flooded in the past and existing flood risk management infrastructure, with new information regarding areas predicted to August 2016 Page | ii be at risk in the future, we have identified those areas of North Lincolnshire which we consider to be at greatest risk from local sources. We intend to focus our attention on managing local flood risks in these areas, to enable efficient and effective solutions to be identified that provide the greatest benefit to our communities. The areas we intend to focus on are set out in this Strategy. The strategy explains the various funding avenues for flood risk management activities and emphasises the need for local partnership and contributions in delivering local flood schemes. Working with our partners, we have already carried out extensive improvement works in many areas. We have contributed jointly to schemes where there have been benefits to all drainage authorities in delivering improvements, and we will continue to do this. For example works to improve a surface water sewer in Ulceby are planned, and include a contribution from Anglian Water, where it has been recognised that benefits to their infrastructure can be jointly derived. Maintaining these new systems, alongside the very important work of maintaining existing drainage networks, is ongoing, and forms part of our annual investment into drainage infrastructure maintenance, which we will continue to undertake across North Lincolnshire. It is also important that private or riparian owners also carry out the routine maintenance they are required to undertake to ensure that watercourses are functioning as intended. When will this occur? This Local Flood Risk Management Strategy is a “live” document, which will continue to be updated as investigation works and analyses continue, improvements are undertaken and future flood events occur. This document then, sets out our strategy for the next six year period, but will remain live throughout that time as further understanding and review influences our priorities within that period. The preparation of this LFRMS is a statutory requirement of the Flood and Water Management Act 2010, where Lead Local Food Authorities must prepare and publish a summary document which considers these risks. This strategy concurs with the Environment Agency’s National Flood and Coastal Erosion Risk Management Strategy. August 2016 Page | iii Contents 1. Introduction 1 1.1 Purpose of this report 1 1.2 Background 1 1.3 Legislative context 2 1.4 Aims and Objectives 3 Overall aims of North Lincolnshire Council 3 Objectives of this strategy 3 Objective 1 – to improve the understanding (of both our communities and our flood risk management partners) of the roles and responsibilities for flood risk management in North Lincolnshire 4 Objective 2 – to improve our understanding of local flood risk 4 Objective 3 – to reduce the risk in our communities from local sources of flooding 5 Objective 4 – seek to implement flood risk management actions that contribute to wider social, economic and environmental outcomes and sustainable development 5 Objective 5 – establish a collaborative approach across stakeholders to address risks from all sources of flooding 5 Objective 6 – raise public awareness and engage with local people about local flood risks, and help our communities to manage their own risks 6 Objective 7 – contribute to planning and development decisions to ensure new development is appropriate 6 Objective 8 – contribute to effective emergency flood response 7 1.5 Related documents 7 National Flood and Coastal Erosion Risk Management Strategy 7 Preliminary Flood Risk Assessment 8 Initial Local Flood Risk Management Strategy - 2011 8 Other relevant Plans and Strategies 9 2. Roles and Responsibilities 12 2.1 Risk Management Authorities 12 North Lincolnshire Council 12 The Environment Agency 13 Internal Drainage Boards 13 Water and sewerage companies 14 Highway Authorities 15 Summary of Risk Management Authorities in North Lincolnshire 16 2.2 Regional Flood Groups 17 North Lincolnshire Council Flood Risk Management Board (the Flood Forum) 17 Flood Risk and Drainage Technical Groups 17 Flood Risk Planning Group 17 Regional Flood and Coastal Committees 18 Humber Local Resilience Forum 18 Humber Local Economic Partnership (Humber LEP) 18 Greater Lincolnshire Local Enterprise Partnership (GLLEP) 18 2.3 Local Communities 18 Flood wardens 19 Local Working Groups 19 Riparian landowners 19 2.4 Internal and External Partners 20 2.5 Flood and Weather Warning Services 21 Flood Warnings 21 National Severe Weather Warning Service 22 Flood Forecasting Centre 22 3. Flood Risk in North Lincolnshire 23 3.1 Historic flood risk 23 3.2 Types of Flood Risk 23 Large scale flooding 23 August 2016 Page | iv ‘Local’ flood risk 24 Other sources of flooding 25 3.3 Factors increasing the risk of flooding 25 3.4 Predicting future flood extents 26 Overview of flood risk in North Lincolnshire 26 Non-‘local’ sources of flooding 26 Local Flood Risk Extents (LFREs) 26 3.5 Prioritisation of risk areas 27 Consequences of future floods – potential receptors 27 Priority categories 29 3.6 Ranking of settlement areas 31 3.7 Settlement area pro-formas 32 3.8 Critical assets located outside of settlement areas 33 3.9 Flood Risk Asset Register 34 3.10 Works Completed to Date 35 Council-wide works 35 Settlement area specific works 35 4. Preferred Strategy for Flood Risk Management 37 4.1 Introduction 37 4.2 Council-wide strategy options 37 4.3 Location-specific strategy options 38 Timeframes 38 Settlement area-specific preferred strategy options 38 4.4 Specific strategy options 40 Surface Water Management Plan 40 Planned capital scheme 41 Investigation of potential capital scheme options 41 Study to increase understanding of drainage/groundwater/watercourse issues at a specific locations 41 Partnership working with Risk Management Partners 42 Telemetry monitoring of specific watercourses 42 Monitor the effectiveness of completed improvements 42 Raised water bodies – monitor with owners 42 Further Investigation and Cleansing 42 Liaison with major industry and Emergency planning in relation to COMAH sites 42 Liaison with owners of critical assets 43 4.5 Other proposed flood risk management strategy activities being led by our risk management partners 43 5.