RTPI Flooding & SUDS. Implementing Flood Management. Christian Lomax - AECOM. Structure of Presentation. Introduction. Background

Transcription

1 RTPI Flooding & SUDS Implementing Flood Management Christian Lomax - AECOM Structure of Presentation Introduction Background Working in Partnership Water Cycle Studies Surface Water Management Plans AECOM & Signet Planning Flood Risk Expertise Planning Expertise

2 Background Flood Risk Management Historically Current Flood Prevention Flood Management Organisations work individually Organisations work collectively The Summer 2007 Floods Flooding Impacts 48,000 houses affected Repair cost up to 30k (total 1.2bn) Average cost to business: 75k to 112k 400,000 pupil days lost Wider Financial Impacts Total Cost to Economy 3.2bn Power & water 325m Local authorities 219m Communications 144m Public Health 287m Emergency services 27m Agriculture 50m

3 The Pitt Review Reviewed Flood Risk Management across England & Wales 92 recommendations for change: local authorities are best placed to understand the risks to and concerns of their communities flood risk management based on partnerships bringing together county, unitary and district authorities, the Environment Agency, water companies and sewerage undertakers and other relevant organisations. Flood and Water Management Act 2010 Framework for managing surface water Sustainable Drainage Duty to cooperate Flood Risk Regulations 2009 Transpose the EU Floods Directive. Aim to reduce the likelihood and consequence of flooding. Requires EU Member States to map flood extent and risk & to take measures to reduce this risk Outcomes Preliminary Flood Risk Assessments Flood Hazard Maps and Flood Risk Maps Flood Risk Management Plans Surface Water Management Plans

4 Working in Partnership Government Strategy Making Space for Water Supports the concept of integrated management of urban drainage. Fund pilot projects to test different approaches to integrated management. Defra s Integrated Urban Drainage Pilot Studies

5 Defra s Integrated Urban Drainage Pilot Studies Runoff from the escarpment NKDC / CoL Runoff from highways LCC Runoff from Properties Private Surface Water Sewers Anglian Water Land Drainage Ditch Riparian Owner IDB Drainage Ditch Upper Witham IDB River Witham Environment Agency Partnership Working Benefits of Partnership Working Acceptance by key stakeholders that they all have a role/responsibility in effective urban drainage. Understanding the legal barriers, policies and procedures of each organisation, and recognising their financial and resource constraints. Data gathering, sharing knowledge, tools and techniques to help identify and assess the interaction of different drainage systems.

6 Barriers to Partnership Working Partnership Issues private and public organisations each with their own policies and procedures. Organisational Issues legal, financial and resource constraints. Data Issues not all organisations obliged to keep records of their assets, lack of surface water models, records lost in handover from LA s to water companies. Who are the Partners? Environment Agency Water Company Local Authorities Drainage Highways Planning Other Stakeholders Water Cycle Studies

7 What is a Water Cycle Study? Ensures development is sustainable. Ensures water infrastructure does not hinder growth. Evidence base for the Core Strategy WCS What does it look at? Water Resources Water Networks & Sewers Sewage Treatment Water Quality Flood Risk Stages of a Water Cycle Study Scoping: Partnership Initial Data Collection Protocols Outline: Initial data review Growth data vs. WC infrastructure Constraints to development identified (and overcome) Detailed: Specific detailed studies to address showstoppers

8 Commissioning a WCS What growth should the WCS consider? All potential growth? Specific sites & housing distribution? County Durham & Newcastle Gateshead Outline WCS Identified Constraints to Development Sewage Treatment Water Supply Water Quality / Environment Now need to identify solutions to support Core Strategies

9 Opportunities Partner Opportunity Appreciation of growth aspirations Northumbrian Water Influence timing & location of development Integrate with strategic infrastructure planning Environment Agency Councils Appreciation of growth aspirations Ensure growth is sustainable Support Core Strategy Ensure growth is not hindered by infrastructure provision Lincoln sustainable villages Lincoln Timeline Lincoln Water Treatment Works Active Leakage Control Pressure Reduction Enhanced Metering Canwick STW Growth Scheme WGC -Mitigation measures to prevent flooding Number of Houses Canwick STW Flow Compliance Scheme NEQ -Direct Sewerage Connection to Canwick STW SEQ -Direct Sewerage Connection to Canwick STW SEQ -Trunk mains for water supply SEQ - max WGC - min NEQ Re-route North Lincoln foul sewerage via NEQ to convert Red sites to Amber 1000 SEQ -Strategic balancing ponds to manage surfacewater 0 AMP5 AMP6 AMP

10 Surface Water Management Plans Surface Water Flooding Who s Responsible? Private Sewers householders, developers, housing association, local authority, water company Reservoirs landowner water company local authority Pitt Review: 60% of 2007 flooding came from overland flow Local Land Drainage & Watercourses landowner (LPAs and IDBs - enforcement & permissive powers. Public Sewers water companies Highway Drainage local authorities (HA, homeowner, developer) Ground Water Flooding Not assigned Designated Main River landowner but (EA - enforcement & permissive powers) Overland Flow Not assigned SWMP Planning Drivers and Context LDF Documents SFRA WCS SPDs SHLAA ELR Surface Water Management Plan Third party data Environment Agency Water Companies Existing Surface Water Flooding Location and design of new development and urban fabric Preparing for emergencies Asset Management Capital Infrastructure and Maintenance

11 What is a Surface Water Management Plan? A framework through which partners with responsibility for surface water and drainage work together to understand the causes of surface water flooding and agree the most cost effective way of managing the risk Very clearly more than just a planning document Implementation and Review Preparation Options Risk Assessment Risk Assessment: Overland Flow Urban areas Flooding from urban fringe (fields, groundwater and pluvial) Modelling (if required) SOURCE PATHWAY RECEPTOR Classify Areas at Low, Medium and High Risk Identify Any Further Work

12 Options High Level Measures for managing the risk Policies Targeted FRM strategies Watercourse Improvements SUDs Managing Surface Water Different Approaches to SWMPs Strategic County Durham Intermediate Newcastle Gateshead & Drain London Detailed Shropshire

13 County Durham SWMP Newcastle Gateshead SWMP Strategic Sites Shropshire SWMP

14 Partnership / Stakeholders Developers Internal Drainage Boards Partners Local Authority Environment Agency Northumbrian Water Local Resilience Forums Highways General Public Summary Summary Introduction to how we got where we are today Partnership Working Water Cycle Studies Surface Water Management Plans

15 Thank You