City of WestminsterLocal Flood Risk Management Strategy (2015-2021)

Consultation Draft April 2015.

Picture credit – Evening Standard

Contents

Executive Summary 31. Introduction 62. Local Flood Risk Strategy Objectives 63. Guiding Principles 64. Why are we doing this? 75. Geographical context 86. Background, legislative, policy and guidance context 87. Flood Risk Regulations 108. Stakeholders 109. Flood risk in Westminster

a. History of floodingb. Sources of flood riskc. Flooding from surface water run-off, groundwater and

sewers.d. Flooding from canals, Water bodies and Water mains

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10. surface water flood risk assessments 1511. Flood Risk Mitigation and Funding 1612. Flood risk asset management in Westminster

a. Recording and Maintaining Assetsb. Designation of assets

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13. Flood Risk Investigation, Response and Recovery 1714. Flood Risk Management through Planning

a. National planning Policy Frameworkb. Westminster City Council policyc. Basement Development in Westminster

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15. Strategic Flood Risk Assessment 2016. Westminster LFRMS Objectives and Action Plan 2015-2020 2117 Funding Strategy 2318 Monitoring and Review 2319 Sustainable development and consistency with other strategies 2320 Timetable and how to comment 24Map 1 Surface Water flood Risk Map 1;100 year event for 1:2 year rainfall event outside WestminsterMap 2 Areas susceptible to elevated groundwaterMap 3 Recorded incidents of sewer flooding in Westminster.

Appendices

Appendix 1 Roles and responsibilities of organisations

Appendix 2 Local flood risk management strategy environmental report

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Executive Summary

Westminster was fortunate to avoid the national floods of 2007. However, after the 2007 floods, the Flood and Water Management Act 2010 was introduced providing legislation for managing flood risk.

The Flood and Water Management Act 2010 gave the City Council new roles and responsibilities. Westminster City Council was designated as a Lead Local Flood Authority (LLFA), with a range of new risk management duties to assess, minimise, mitigate, manage and monitor flood risk.

In our role as the LLFA, we are required to develop, maintain, apply and monitor a strategy to manage surface water run-off and groundwater in Westminster. Westminster does not contain any ordinary watercourses.

This Local Flood Risk Management Strategy (LFRMS) sets out how Westminster, in partnership with other stakeholders will manage flood risk. It identifies where flood risk is greatest in Westminster and the responsibilities stakeholders have to manage it. It also sets out specific actions to reduce the risk of flooding in areas at greatest risk

These objectives and actions are

Its objectives are

The LFRMS has been developed using evidence and analysis of flood risk, through consultation, and assessment against environmental objectives and assessment sub-criteria.

Table 1 lists the Key Actions for 2015 to 2020 that will help meet the aims and objectives of the LFRMS.

Table 1: Key Actions for 2015-2020

LFRMS 1 Actions: Tackling sources of flooding from highways

HIGH 1 Publication of most significant flood risk assets in Westminster

HIGH 2 Designation of significant flood risk assets to ensure that they are maintained.

HIGH 3 Manage and Maintain drainage assets

LFRMS 2: Tackling flood risk through planning and development

DEV 1: Provide Technical advice and promote SUDS through planning and development

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To understand and explain the level of risk affecting Westminster;

To understand the roles of partners, businesses and residents in Westminster to manage flood risk.

To take a sustainable and holistic approach to flood risk management; and

To provide an action plan for flood risk management in the city

DEV 2:Develop flood risk policy to manage, mitigate and adapt to flood risk

DEV 3 Review and Revise Strategic Flood Risk Assessment, as new data becomes available, or

on a 6 yearly cycle, whichever is more appropriate.

DEV 4: Review and revise Local Flood Risk Management Strategy and Flood Risk Management

Plan on a 6 yearly cycle.

DEV 5- Use LFRMS to inform development of Local and Neighbourhood and development plans,

drainage management and maintenance plans and programming: contingency plans and asset

management plans

LFRMS 3 Tackling flood risk through Raising Awareness

AWARE 1 Modelling Surface Water Flood Risk

AWARE 2 Prepare Flood Risk Awareness Communications Plan

AWARE 3 Publish significant flood incident reports

AWARE 4 Publish significant flood risk asset register.

LFRMS 4 Tackling flood risk through Partnership working

PART 1: Work in partnership with other flood risk management authorities, stakeholders and

relevant departments to address flood when it happens, and ensure contingency plans is

appropriate.

PART 2: Work with Thames Water and other key stakeholders to mitigate and manage flood risk

from surface water and manhole surcharge in Westminster,

Part 3 :Organise, attend and participate in flood risk management meetings such as Drain

London/LoDeg, London Central North Flood Risk Group and Westminster City Council’s flood risk

management group

LFRMS 5:Flood Risk Management and Maintenance

RISK 1: Seek opportunities for Sustainable Drainage Systems across the city

RISK 2: Implementation of LFRMS and action plan

RISK 3 Identify and prioritise programme of flood risk management projects and funding for 2015-

2020 and provide multiple benefits in terms of biodiversity, amenity, health and wellbeing.

The Flood and Water Management Act 2010 identifies the City Council, the Environment Agency and Thames Water Utilities Limited as the major risk management authorities for Westminster with new responsibilities.

Additionally, the following other stakeholders have also been identified as key stakeholders in Westminster.

Residents and businesses Greater London Authority/Transport for London

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Neighbouring London Boroughs Network Rail Canal and River Trust.

These key stakeholders and the public will be consulted on the draft strategy and comments received will be considered when finalising the strategy.

The Strategy is a ‘living’ document, and will evolve as new evidence is produced and understanding increases. The action plan will be monitored and reviewed annually as part of the annual monitoring report and will be fully reviewed every 6 years.

Environmental assessment of the strategic objectives and actions are presented in the Environmental Report (Appendix 2). Significant beneficial effects on implementation of the strategy are

Improved flood risk management for local residents, businesses, workers and recreational users, and tourists and reduced flood risk to critical infrastructure.

Encourages partnership working Improves understanding, preparedness and response and recovery from flooding

and potentially reduce fear of the flooding. Provides opportunities to deliver wider environmental and social benefits in terms of

biodiversitiy, amenity etc.

Although it is uncertain what impacts new flood risk management schemes will have on the historic environment or townscape and public realm, until detailed designs have been completed

We are now consulting on the draft strategy and it is available online at

https://www.westminster.gov.uk/council-open-consultations

The strategy is available for consultation from April 27th to June 5th 2015.

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1 Introduction

1.1 The Flood and Water Management Act 2010, gave the city council strategic responsibility for managing flood risk from surface water, groundwater and ordinary watercourses.

1.2 This Local Flood Risk Management Strategy (LFRMS) sets out how Westminster, in partnership with other stakeholders will manage flood risk. It identifies where flood risk is greatest in Westminster and the responsibilities stakeholders have to manage it. It also sets out specific actions to reduce the risk of flooding in areas at greatest risk.

1.3 The work identified in this strategy will help to reduce flood risk but cannot stop floods happening. All stakeholders will need to work together to reduce the likelihood of flooding and the impact of flooding if it were to happen. This is why it is important that all residents, businesses and other institutions are aware of their roles and responsibilities (Appendix 1).

2 Local Flood Risk Management Strategy Objectives

2.1 The LFRMS objectives are

1. To understand and explain the level of risk affecting Westminster;

2. To understand the roles of partners, businesses and residents in Westminster to manage flood risk.

3. To take a sustainable and holistic approach to flood risk management; and

4. To provide an action plan for flood risk management in the city

3 Guiding principles

3.1 The following guiding principles inform Westminster’s overall approach to managing flood risk.

Flooding is a natural event that will sometimes occur despite all efforts to prevent it. It is important therefore, to focus on installing flood resistance and resilience measures.

Effective flood risk management can reduce long term flood damage costs and is a worthwhile investment for both the public and private sector.

Decisions on where local resources will be focussed are evidence based Improving knowledge and understanding of flood risk is vital for all No single organisation can effectively manage flood risk alone, co-operation is

necessary from public and private sectors and residents. Objectives have been set taking account of local knowledge, modelling and mapping

and evidence gathering, as set out in SFRA 2010, enhanced surface water flood risk modelling, and calibrated sewer modelling of critical drainage hotspots in Westminster 2014/15, along with the Westminster’s vision of a City for All, Westminster City Council’s Strategic Policies and Integrated Impact Assessment It also takes account of the need to integrate our role as a Lead Local Flood Authority with our roles as Local Planning Authority, Highways Authority, Contingency Planning, Asset Management and Policy, Performance and Communication

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4 Why are we doing this?

4.1 Westminster was fortunate to avoid the national floods of 2007. However, after the 2007 floods, the Flood and Water Management Act 2010 was introduced providing legislation for managing flood risk.

4.2 The Flood and Water Management Act 2010 gave the City Council new roles and responsibilities. Westminster City Council was designated as a Lead Local Flood Authority (LLFA), with a range of new risk management duties to assess, minimise, mitigate, manage and monitor flood risk.

4.3 In our role as the LLFA, we are required to develop, maintain, apply and monitor a strategy to manage surface water run-off and groundwater in Westminster. Westminster does not contain any ordinary watercourses.

4.4 A review of this strategy will take place by June 2020 in consultation with key stakeholders. A fuller review, with public consultation will then take place on the National Flood Risk Management Plan 2021. In the event of either a major flooding incident or a significant change in legislation, the timing of this may be reviewed.

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5 Geographical Context

5.1 The City of Westminster is located in north London and covers approximately 21.5km2

(Map 1) . It sits between the London borough of Brent to the north, City of London and London Borough of Camden to the east, the tidal Thames to the south and the Royal Borough of Kensington and Chelsea to the west.

6 Background; Legislative, Policy and Guidance

International, National, Regional and Local Plans and Programmes

6.1 Relevant international, national, regional and local plans and programmes have been identified and considered in the preparation of this strategy. The key relevant plans are listed in Table 1 below and a full list of releveant plans and programmes can be found in the SEA Environmental Report Appendix B.

Table 1 – Relevant Plans and programmes .

InternationalFloods Directive 2007/60/ECWater Framework Directive 2000/60/ECGroundwater Directive 2006/118/ECStrategic Environmental Assessment (SEA) Directive 2001/42/ECHabitats Directive 1992/43/ECNationalFlood and Water Management Act 2010Flood Risk Regulations 2009National flood and Coastal Erosion Management (FCERM) Strategy for England 2011 (EA& DEFRA)National Planning Policy Framework (NPPF) 2012 (DCLG)Technical Guidance on National Planning Policy Framework 2012 (DCLG)National Planning Practice Guidance 2013 to NPPFDraft SUDs National Standards.RegionalThe London Plan 2011The Mayor’s Water Strategy 2011The Mayor’s Climate Change Adaptation Strategy 2011Thames Estuary 2100 2012Thames River Basin Management Plan 2009LocalCity of Westminster Strategic Flood Risk Assessment 2010City of Westminster Preliminary Flood Risk Assessment 2011Westminster City Plan – Strategic Policies 2014

6.2 The Floods Directive requires Member states to assess the risk of flooding and to identify measures in place to reduce that risk. The Water Framework Directive requires protection of water bodies, including the River Thames with the aim of achieving ‘good’ water quality status by 2015. The Groundwater Directive sets the framework for the protection and

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conservation of groundwater. The SEA and Habitats Directive requires the assessment of impacts of plans and programmes to identity their effects on the Environment and Designated European sites.

6.3 Nationally, the Flood And Water Management Act (FWMA)2010 , designated the City of Westminster as a Lead Local Flood Authority (LLFA), responsible for managing local flood risk from surface water, groundwater and ordinary watercourses. The Environment Agency retained responsibility for managing flood risk from the sea, main rivers and reservoirs.

6.4 LLFA’s duties include,

Strategic management of local flood risk Power to request information related to flood incidents and flood risk to investigate and publish flood incident records the designation of flood management assets and maintenance and publication of

flood risk asset register powers to do works to manage surface water and ground water flood risk; and the production of a Local Flood Risk Management Strategy.

6.5 Section 9 of the FWMA 2010 also requires LLFAs to

“develop, maintain, implement and monitor a strategy for local flood risk management in its area covering surface water runoff, groundwater and ordinary water courses”. The strategy must specify the following

the risk management authorities in the area and their flood and coastal erosion risk management functions

the assessment of flood risk the objectives for managing local flood risk and measures to achieve those

objectives, including their implementation, cost and benefits and how they will be paid for:

How and when the Strategy is to be reviewed, and how it contributes to the achievement of wider environmental objectives.

6.6 The Strategy must be consistent with the Water Framework Directive ( UK Regulations 2003 ), the National Flood and Coastal Erosion Risk Management Strategy for England (DEFRA 2011) and should be consulted on publically. Consistency with the national strategy means consistency with the overall aims and objectives, in particular

community focus and partnership working; a catchment and coastal “cell” based approach; sustainability ; proportionate, risk based approaches (identify the highest risks and the priorities for

taking action); multiple economic , environmental and social benefits; and beneficiaries should be allowed and encouraged to invest in local flood risk

management.

7 Flood Risk Regulations (FRR) 2009 4

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7.1 The FRR imposed a duty to prepare and publish a series of flood risk documents including a Preliminary Flood Risk Assessment, Flood Risk Maps and Flood Risk Management Plans. The City Council has produced these documents in partnership with the Environment Agency and Drain London.

7.2 The Strategy also needs to take account of the links with the Civil Contingency Act 2004, which delivers a single framework for civil protection in the UK, and the planning system. Through the planning system flood risk will be taken into account when development is proposed, and from April 6 2015, where appropriate, the implementation of Sustainable Drainage Solutions will be sought through development planning .

7.3 Other plans, strategies and documents taken into account when preparing this document were

WCC Strategic Flood Risk Assessment 2010 WCC enhanced surface flood risk modelling 2015 Framework to assist the development of the Local Strategy for Flood Risk

Management ‘ A living document’ ( Local Government Association 2011) WCC Preliminary flood risk assessment 2011) ; London Regional Flood Risk Appraisal First Review ( Greater London Authority 2014) WCC draft Surface Water Management Plan 2011

Multiagency Flood Plan 2013 WCC strategic policies – City Plan 2013 National Planning Policy Framework 2010

7.4 Flood risk management is an environmental activity and the strategy needs to support both local and national flood risk management plans and the need for sustainable development and ensure that it satisfies the needs of today while making sure that future generations can also look forward to the same quality of life.

7.5 It does this by considering key national plans such as the Water Framework Directive and Strategic Environmental Assessment (SEA) Directive, as well as local plans such as Integrated Impact Assessment (IIA). More information on these plans can be found in Appendix 2 ( Local Flood Risk Management Strategy Environmental Report 2015 )

8 Stakeholders

8.1 The Flood and Water Management Act 2010 identifies the City Council, the Environment Agency and Thames Water Utilities Limited as the major risk management authorities for Westminster with new responsibilities.

8.2 Additionally, the following other stakeholders have also been identified:

Residents and businesses Greater London Authority/Transport for London Neighbouring London Boroughs Network Rail Canal and River Trust.

A list of key stakeholders and their roles and responsibilities can be found in Appendix 1

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9 Flood Risk in WestminsterHistory of Flooding9.1 No major flooding incidents have been recorded in Westminster in recent history. However, Westminster is at risk from a number of sources of flooding

Sources of Flood Risk9.2 The most likely sources of flooding in Westminster are listed below

Flooding from the River Thames Flooding from surface water Flooding from sewers Flooding from groundwater Flooding from canals, water features and water bodies

9.3 Flooding from the River Thames and from surface water has been identified as posing the most likely risks in Westminster. This strategy takes account of the risk from surface water, ground water, sewers, canals, water features and water bodies.

Flooding from Surface Water Runoff, groundwater and sewers9.4 As a Lead Local Flood Authority we are tasked with managing flood risk from Surface Water run-off (i.e. rainwater that is on the surface of the ground and has not entered the watercourse, drainage system, or combined sewer), ground water or flooding from sewers which are full be capacity due to heavy rainfall. Westminster does not contain or manage any ordinary water courses. Map 1 shows a 1:100 surface water flood risk map for 1:2 year rainfall event outside Westminster. Flood Risk Areas can be identified from this mapping which was undertaken in March 2015.

9.5 The risk of groundwater flooding in Westminster is uncertain and more information is required to improve understanding of it. Groundwater flooding occurs when the water table rises to the ground surface and inundates low-lying areas. There are a number of underground stations and basements that need to pump excess groundwater to prevent flooding. The risk of groundwater flooding in Westminster is considered to be low, however, Westminster sits above a chalk aquifer covered with gravels and clay. Chalk shows some of the largest variations in groundwater levels and in low-lying areas this may be an issue in the future. Deep basements in the city in some areas require continuous pumping of excess groundwater. Areas susceptible to groundwater flooding are shown in Map 2 .

9.6 Sewer flooding and manhole surcharge are also possible sources of flooding in the city which may be caused by excess surface water entering the drainage system after a heavy downpour. Map 3 shows a map of recorded incidents of sewer flooding in Westminster.

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Map 1 Surface Water flood risk map March 2015

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Map 2 Areas susceptible to elevated groundwater.

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Map 3 Recorded Incidents of Sewer flooding in Westminster.

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Flooding from Canals, Water Bodies and Water Mains 9.6 In Westminster this type of flooding is most likely to result from burst mains from infrastructure failure in an artificial watercourse or water bodies i.e. canals or other water features. 9.7 There are a number of canals and water bodies in Westminster , these include

Paddington Branch of Grand Union Canal, including Paddington Basin and Little Venice,The Regent’s CanalSerpentine Hyde ParkRegents Park LakeSt James’s Park LakeKensington Gardens Lake and Five ‘hidden river’s ‘, the Westbourne, Tyburn, Tyburn Brook, Kilbourne and Long Ditch.

9.8 As extreme rainfall events do not happen regularly but cause serious damage when they do occur, it is essential to model the effect of such rainfall event on the city. This is particularly important because climate change is predicted to increase the likelihood of major rainfall events. However, it would be risky to rely totally on modelling, which is why it is important that any significant flood events are fully investigated.

10 Westminster Surface Water Flood Risk Assessments 10.1 The surface water flood risk modelling process started with Drain London, the GLA programme to improve understanding of surface water flood risk in Greater London, Drain London helped to deliver Preliminary Flood Risk Assessments and Surface Water Management Plans for each London Council. This process helped to provide a consistent baseline across London. Subsequently, in 2014, Westminster commissioned WSP to undertake an Initial Assessment of surface water flood risk in Westminster using a calibrated Thames Water Sewer model. This study identified those areas most at risk from surface water flooding and where we will need to focus our resources in the future. These are

Pimlico south,

Pimlico north and Victoria,

Marylebone and Mayfair,

Westbourne Grove,

West Kilburn, and

Maida Vale.

10.2 Identifying where the greatest risk of surface water flooding helps us focus our approach to flood risk management in the city. Appendix 3

10.3 This advanced enhanced modelling has provided the evidence base necessary to secure funding for full Environment Agency Project Appraisal Reports for the whole of the city.

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11 Flood Risk Mitigation and Funding11.1 Defra provides Grant in Aid for capital schemes through Partnership funding whereby all flood risk mitigation schemes are offered a fixed subsidy based on the benefits delivered by scheme. .

11.2 To access funding the Council must apply to the Environment Agency’s Thames Regional Flood and Coastal Committee with programmes to improve understanding of flood risk and schemes to reduce flood risk. The Initial Assessment of surface water flood risk provides the evidence base for future Partnership funding applications to deliver flood risk capital schemes.

11.3 The City Council has been allocated a provisional sum of money for capital schemes should full project appraisal reports conclude they are feasible and economically viable. If the partnership funding score is 100% no further contributions will be required and work can commence. If, however, the partnership funding score is less that 100% external funding from other stakeholders such as landowners, businesses and Thames Water, will need to be sought.

11.4 Funding may also be sought from Thames Local Levy, which is a fund all local authorities from the Thames Region pay into.

11.5 The purpose of the partnership funding model is to promote further private investment. The scheme aims to encourage communities to take more responsibility for managing flood risk and aims to deliver greater environmental benefit by encouraging total investment to increase beyond the levels that DEFRA alone can afford.

11.6 Once funding has been secured and the business case has been developed, the City Council will commission its contractors to undertake schemes.

12 Flood Risk Asset Management.12.1 This section explains how Westminster will manage its flood risk assets through the following activities

Recording and maintaining assets Investigating and reporting flood incidents

Recording and maintaining assets 12.3 Flood Risk Assets are all structures or physical features that have an effect on flood risk in the city, from reservoirs to highway gullies. The recording and maintenance of flood risk assets is an important element of flood risk management because well maintained assets , such as drainage systems , ensure that water flows directly away from buildings and critical infrastructure.

12.4 Well maintained assets cannot prevent flooding but they can lessen the impacts and likelihood. Thames Water constructs sewers to a 1:30 flood event, when a rainfall event happens which is less probable than this , sewers are likely to overflow causing flooding. Modelling has indicated that some areas in Westminster could see manhole surcharges for a 1:10 flood event. These are at particular risk of flooding.

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Asset register and records 12.5 As the LLFA, Westminster is obliged to establish and maintain a register of structures or features which are likely to have a significant effect on flood risk in the city. This must be available to inspection at all reasonable times. Westminster must also produce a record detailing the ownership and state of repair of each asset, which is not publically accessible.

12.6 The LLFA must determine the criteria for deeming an asset as have a significant effect. In Westminster assets are deemed to be significant if it is:

Of such a significant size that its failure could cause drainage problems on its own: or Located within an area considered to be at a relatively high probability of flood risk.

12.7 The register stating assets in the city will be published on our website and will be updated annually with new assets and changes in ownership recorded. The record will be shared with all the organisations which have contributed data to it.

Maintaining assets12.8 Asset owners are responsible for maintaining their own assets. City Council flood risk assets would be managed and maintained by its Infrastructure and Asset Management Group.

Designation of assets12.9 The City Council and the Environment Agency are the ‘designating ‘authorities for flood risk assets. This is, the City Council may ‘designate’ features and structures as flood risk assets. If an asset is designated, its owner cannot alter or remove it without first consulting the designating authority. The aim of designating flood risk assets is to safeguard them against unchecked works which could increase flood risk in the city. It is not possible to designate assets owned by a risk management authority, such as Thames Water, although this does not diminish their responsibilities for maintaining them as asset owners. A process for designating assets will be designed in partnership with neighbouring authorities to ensure that there is consistency across London.

13 Flood Incident Investigation, response and recovery. Flood Incident Investigation 13.1 As the LLFA we have a responsibility to produce a flood investigation report for any significant flood incidents. The decision as to whether a flood event is significant or not is at the discretion of the LLFA, current understanding is that the following two criteria should be met

The incident resulted in internal flooding of a property: and/or If there is ambiguity surrounding the source or responsibility for the flood ( e.g. it is

unclear if it is a burst main)

13.2 Investigations will involve consultation with the relevant stakeholders, residents, landowners and private organisations, all of whom have a duty to co-operate with the City Council and provide comments. A flood investigation report will be produced for any incident and will be published as required by the Flood and Water Management Act 2010. Reports will seek to provide a clear and thorough understanding of the flooding situation.

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13.3 There is no obligation on any organisation to deliver flood defence or mitigation schemes to residents or businesses that are at risk of flooding. New developments need to be designed to be resilient to major flood events and new major developments will be required to present site drainage management plans when submitting a planning application. The Site Specific Sustainable Drainage Management plans will undergo technical review by the LLFA, who will provide comments to the Local Planning Authority. These comments will be taken into account as a material consideration when the planning decision is made.

Responding to flood incidents 13.4 Flooding comes from different sources and has differing impacts depending on the scale of the flood event. Given this, flood incidents are categorised as follows

Ponding –this occurs after a heavy downpour and is characterised by puddles of water on roads and footpaths that have neither drained nor evaporated. The water is neither causing serious disruption nor threatening buildings or critical infrastructure.

Disruptive flooding- this flooding impacts on peoples movements and ability to carry out normal tasks by blocking roads or cordoning of flooded area, or is flowing at such rates as to cause danger to people.

Damaging or Dangerous flooding – This is flooding that enters buildings or critical infrastructure causing damage or is flowing at such a rate as to cause serious danger to people..

13.5 Preparation for responding to ‘damaging or dangerous’ flooding is part of the emergency response planning and the multiagency flood plan, of which there are two main elements , response and recovery.

Response to major flooding incident 13.6 The City Council’s Civil Contingency Team will work with local emergency services to implement the Multiagency Flood Plan which provides a co-ordinated response to major flood incidents to ensure rapid response and recovery and reduce impacts on people.

13.7 In the event of a major flood incident it is impossible for local emergency services to be able to help everybody and it will prioritise preservation of life, and seek to help those more vulnerable.

Recovery from major a flooding incident 13.8 The City Council will seek to begin recovery procedures as soon as possible after a major flood incident. As flood water recedes, the emergency response may still be going on, as the recovery phase is initiated. If it is a minor incident, recovery activities such as street cleaning will for part of normal operations. If it is a severe flood it will require a co-ordinated effort to determine local strategies in recovery, prioritising needs and allocating resources appropriately so that the community returns to normality as soon as possible.

14 Flood Risk Management through planning 14.1 It is vital for good flood risk management that new developments are safe from flood risk and does not increase flood risk elsewhere. Planning policy is led by the City Council in its role as the Local Planning Authority. The Lead Local Flood Authority advises the Local

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Planning Authority on site specific flood risk assessments and sustainable drainage management plans for major development sites and sites of > 1 hectare.

National Planning Policy Framework14.2 The National Planning Policy Framework (NPPF) state that inappropriate development in areas at risk of flooding should be avoided by directing development away from areas at highest risk and, where development is necessary, it should be made safe without increasing flood risk elsewhere.

Westminster City Plan: Strategic Policies 201314.3 Westminster City Plan ; Strategic Policy S30 Flood Risk identifies our approach to flood risk management and seeks to ensure that all sources of flooding are taken into account and that potential flood risk is reduced through mitigation measures. Relevant London Plan Policies include Flood Risk (5.12) and Sustainable Urban Drainage (5.13 ”.

14.4 Implementation of Schedule 3 of the Flood and Water Management Act 2010 as of April 6th requires the submission of Sustainable Drainage Management Plans along with any major planning application submitted to the Local Planning Authority. The Local Planning Authority is then required to consult the Lead Local Flood Authority for Technical Advice on the Sustainable Drainage Management Plan, and to take account of LLFA comments as a material consideration when making a decision on the application.

Basement development policy in Westminster 14.5 Westminster’s adopted Basement Development in Westminster 6.3.6 states that“ 6.3.1 Cellars and basements can be vulnerable to flooding. Such flooding can come from a number of different sources, including overflowing drains and nearby watercourses, groundwater flooding and surface water flooding.6.3.2 It is important to establish whether there is a significant flood risk before deciding to go ahead with an application for basement excavation or conversion and you should first determine whether the application property is located in a flood risk zone or within a surface water hotspot”. It would also help to consider if the basement is in an area susceptible to groundwater flooding “ the construction of a basement under a garden may reduce the infiltration capacity of the ground and could therefore result in additional surface water run-off from the site as well as reduce capacity of the ground to act as a store for rainwater. Wherever possible, self-contained basement dwellings should be located outside of surface water hotspots . If building a basement extension in any area prone to surface water flooding steps should be taken to avoid increasing ( and where possible reduce) surface water flood risk for the site and beyond. A number of sustainable drainage measures can be used to reduce the surface water run-off from a site including rainwater tanks, permeable paving and living roofs. Retrofitting of Sustainable Drainage systems will be encouraged where appropriate. Applicants should also show they have had regard to the London Plan and justification provided where this is not practical or appropriate6.3.7 In flood risk areas, where permeable surfacing and sustainable urban drainage measures are recommended in the flood risk assessment or structural statement, the council may secure their installation and retention by condition. Sewer and groundwater flooding 6.3.8 Basements may be more susceptible to sewer flooding and this should also be considered by the structural or civil engineer. As a minimum, it is recommended that all

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drainage connections from basements to sewers should be fitted with a one way valve to prevent drains flooding the basement if they surcharge. During periods where drains are surcharged, the drainage system may not work. Basement designers should consider installing pumped sewerage system to protect against this, particularly in areas where there is an increased sewer food risk6.3.9 Our technical evidence shows that most basement development is unlikely to impact on, or be affected by groundwater flooding. However there may be an impact where the basement floor level extends into or close to existing groundwater. Particular care is needed in designing basements where:

Basements extend through the gravels below the perched water table into the underlying London Clay or which have their lower levels close to the level of Upper Aquifer (within 300mm of it )

Basements are in the vicinity of the historic routes of the Westbourne and Tyburn Rivers and their tributaries.

New basements proposed to existing houses with basements or lower ground floors, where the existing perched water level is close to the lowest occupied area of existing buildings

6.3.10 We will expect these issues to be assessed, monitored and addressed by thestructural engineer undertaking the basement design. However, it is often a combination of the above types of flooding that leads to increased flood risk and the engineering design should take account of the specific combinations of geo-hydrological conditions on the site. This should be considered in the structural statement…”

“Flood Resistance and Resilience6.3.11 In all basement development, applicants are encouraged to incorporate floodresistance and resilience measures as part of the design. This includes measures to prevent water ingress and to reduce flood damage should flooding occur. These may include, for example, setting all thresholds to basements to be above the flood level and incorporation of one way valves, incorporation on internal staircases and means of escape and placement of electrical circuits to minimise potential for damage.”

Strategic Flood Risk Assessment14.6 As a Local Planning Authority, the City Council is required to produce a Strategic Flood Risk Assessment (SFRA) as the evidence based for the Local Plan. We produced an SFRA that was published in 2010 and can be found at http://www3.westminster.gov.uk/docstores/publications_store/SFRA_Final_Main_Report_May10.pdf .

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15 Westminster LFRMS Objectives and Actions 2015-2021

15.1 The Local Flood Risk Management Strategy objectives between 2015 and 2021are

15.2 The Actions identified to achieve these objectives are

Action LFRMS1 Tackling Flooding through highways management

Action LFRMS 2 Tackling flood risk through Planning and Development

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To understand and explain the level of flood risk affecting Westminster

To highlight the actions that all partners, businesses and residents will need to

take to manage flood risk

To take a sustainable and holistic approach to flood risk management,

seeking to deliver wider environmental and social benefits

To provide an action plan to address particular areas at risk from surface

water flooding

HIGH 1 Publication of most significant flood risk assets in Westminster

HIGH 2 Designation of significant flood assets to ensure they are maintained

HIGH 3 Manage and Maintain Drainage Assets

DEV 1 Provide Technical Advice on SUDs through planning

DEV 2 Develop flood risk policy to manage, mitigate and adapt to flood risk

DEV 3 Review and revise Strategic Flood Risk Assessments, as new data

becomes available or on a 6 yearly cycle, whichever is more appropriate

DEV 4 Review and revise Local flood risk management Strategy and Flood

Risk Management plan on a 6 yearly cycle.

DEV 5 Use LFRMS to inform development of Local and Neighbourhood

Development Plans, Drainage management and Maintenance Plans and

programming; contingency plans and asset management plans.

Action LFRMS 3 Tackling flood risk through improved understanding and raising awareness

Action LFRMS 4 Tackling flood risk through partnership working.

Action LFRMS 5 Flood Risk Management and Maintenance

16 Funding Strategy

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AWARE 1 Modelling Surface Water Flood Risk

AWARE 2 Prepare Flood Risk Awareness Communications Plan

AWARE 3 Investigate and publish significant flood incident reports

AWARE 4 Publish significant flood risk asset register.

PART 1 Work in partnership with flood risk management authorities, stakeholders

and relevant departments to address flood when it happens, and to ensure

contingency plans are appropriate.

PART 2 Work with Thames Water and other key stakeholders to mitigate and

manage flood risk from surface water and manhole surcharge in Westminster,

PART 3 Organise, attend and participate in flood risk management meetings

such as Drain London/LoDeg, London Central North Flood Risk Group, internal

Flood Risk Management Group,

RISK 1 Seek opportunities for Sustainable Drainage Systems across the city.

RISK 2 Implementation of Local Flood Risk Strategy and Action Plan

RISK 3 Identify prioritised programme of flood risk management projects and

funding for 2015-2020 and provide multiple benefits in terms of biodiversity,

amenity, health and wellbeing.

16.1 The main source of flood risk in Westminster is from surface water flooding and possible interaction with sewer flooding leading to manhole surcharges in certain areas. Therefore, any actions will focus on understanding, mitigating and managing the risk, and increasing resilience and resistance to flood risk in the city.

16.2 Flood risk management funding is available both nationally and locally.

16.3 Nationally Defra provide a direct grant to Lead Local Flood Authorities.

16.4 Funding for technical advice on surface water drainage proposals has also been allocated to Lead Local Flood Authorities to carry out their duties as a consultee on major planning applications from April 16 2015.

16.5 Local flood risk funding is also allocated via the Thames Regional Flood and Coastal Committee through Levy Funding and/ or through Environment Agency’s Flood Defence Grant in Aid (FDGiA). These funds may be accessed by a bidding process in which the the need for the project and a Cost Benefit Analysis of the project must demonstrate how it will reduce the number of properties and people at risk of flooding.

16.6 Funding may also be allocated by Highways Authorities, Local Planning Authorities Community Infrastructure Levy for public realm and flood risk projects benefiting more than one sites, and section 106 funding for individual development sites if the need and the relationship with developments is proven.

16.7 Opportunities will also be sought to find alternative sources of funding. Beneficiaries of flood risk management schemes will be encouraged to invest in those schemes.

17 Monitoring and Review17.1 Implementation of the strategy and action plan will be monitored reviewed. The results will be reported in the Annual Monitoring Report produced by Westminster City Council.

18 Sustainability and links with other strategies and Frameworks

18.1 This document is consistent with the National Flood Risk Strategy’s overall aims and objectives of

A community focus and partnership working A catchment based approach Sustainability Proportionate, risk based ( actions prioritised for areas at highest risk) Multiple economic, environmental and social benefits; and Beneficiaries should be allowed and encouraged to invest in local flood risk

management.

18.2 The strategy also takes account of the Water Framework Directive, the Thames River Basin Management Plan and the Local Flood Risk Strategy Strategic Environmental Assessment (Appendix 2).

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18.3 It is clear when assessed against the LFRMS SEA objectives, that implementation of the strategy will help achieve water quality as well as flood risk management objectives. Given that the strategy will not impact on any designated European Designated Sites it was concluded that a Habitat assessment was not required.

19 Timetable and how to comment

19.1 Comments are invited on this draft Local Flood Risk Strategy and its Environmental Report by June 5th 2015.

Comments may be sent to D James, Westminster City Council.

Email – djames1@westminster.gov.uk Post – D James , Infrastructure Asset Management Group

o 11th floor o City Hallo 64 Victoria Streeto SW1E 6QP

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Appendix 1

Stakeholder roles and responsibilities

Risk Management Authorities

The following organisations are recognised as Risk Management Authorities under the FWMA 2010.

Lead Local Flood Authorities

The Environment Agency

Water Companies

Highways Authorities

Internal Drainage Boards (not applicable in Westminster)

District and County Councils ( not applicable in Westminster).

The key RMAs in Westminster are

City of Westminster

Environment Agency,

Thames Water and

Transport for London.

All RMA’s have the following duties and powers.

1) Duty to subject to scrutiny from lead local flood authorities’ democratic processes. They can be called to account for their actions by the Culture and Environment Scrutiny Committee

2) Duty to co-operate with other RMAs in the exercise of their flood and coastal erosions risk management functions, including sharing flood risk management data;

3) Power to take on flood risk functions from another risk management authority when agreed by both sides.

1 City of Westminster

The City of Westminster under the FWMA 2010 was designated as a Lead Local Flood Authority for its administrative area.Thus Westminster has a strategic role in overseeing the management of surface water and groundwater flood risk along with the following new powers:

To do works to manage flood risk from surface water or groundwater: To designate structures and features that affect flooding; To request information from any person in connections with the authority’s flood and

coastal erosions risk management functions.

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It also gives LLFAs the following responsibilities

Strategic Leadership – bringing together stakeholders and leading on developing a strategy to manage flood risk in the city.

Meeting flood risk regulations

Producing flood investigation reports

Maintaining register and records of assets

Designating assets

Recording flood incidents

Implementing SUDs through planning.

As well as these new roles, the City of Westminster has other longstanding responsibilities which play and important role in flood risk management. These include:

Responsibilities as a planning authority

Responsibilities as a highways authority

Responsibilities for civil contingency planning

Responsibilities for parks and open spaces

Responsibilities for social housing.

2 Thames Water

Thames Water is responsible for supply and drainage of water in Westminster and has the following flood risk management responsibilities to

Provide, maintain and operate systems of public sewers and works for the purpose of effectively draining an area, including maintenance of all drains which serve more than one property or which extend beyond the curtilage of the property.

Respond to flood incidents involving their assets.

Undertake capacity improvements to alleviate sewer flooding problems with priority being given to frequent internal flooding problems.

Adopt all new lateral drains and sewers that are to connect to the public sewer from April 2013

Statutory consultee to LPA for Sustainable Drainage Management Plans for major developments.

Maintain its reservoirs according to the standards of the reservoir act.

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Thames Water does not have responsibility for highways or land drainage until the surface water enters the combined sewer network in Westminster, nor does it have responsibility for drainage within a property or serving one property.

3 Environment Agency (EA)

The EA has a strategic role in flood risk management for England with responsibilities to

Publish a National Flood Risk Management Plan which provides a clear national framework for all forms of flood risk management

Managing regional flood and coastal committees (RFCC) and support their decisions in allocation funding for flood defence and flood resilience schemes

Review and supporting LLFAs

Providing data and information and tools to inform government policy and aid RMAs in delivering their responsibilities.

Reporting and monitoring flood and coastal erosions risk management .

Operationally the EA focuses on flooding from main rivers and the sea, which includes the Tidal Thames in Westminster. It also is a statutory consultees for all planning applications in flood zone 3 and the enforcement authority for reservoirs greater than 10,000 m3

It also maintains and publishes a register of reservoirs.

4 Transport for London (TfL)

Transport for London is responsible for the Strategic Road Network in Westminster. It is responsible for London Underground and gullies and culverts and for ensuring that these assets do not cause flood risk. TfL are a RMA.

Other key stakeholders

5 Residents and businesses

It is the responsibility of residents and businesses to look after their homes and properties, including protecting them from flooding. Which in some circumstances other organisations or property owners may be liable due to neglect of their own responsibilities, although there will be occasions where flooding happens despite all parties carrying out all of their duties and responsibilities.

It is therefore suggested that residents and businesses at ground or basement level may wish to consider

Flood insurance

Flood resistance and resilience measures

Prioritising what would be important to save at times of flooding

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Identify who can help them and who they can help in the event of a flood, or any emergency; and

To make a flood plan (www.environment-agency.gov.uk) and prepare a flood kit.

Some areas have a higher risk of flooding than others and it is important that we help businesses and residents understand that risk and consider protection measures, resistance and resilience measures in preparation for a possible flood event.

Westminster will seek to deliver capital schemes to mitigate flood risk in areas identified with the greatest risk.

6 Greater London Authority (GLA)

The GLA is not a LLFA and has no statutory role in flood risk management. However it developed Drain London to improve knowledge of flood risk in London and helped Westminster prepare its Preliminary Flood Risk Assessment and draft Surface Water Management Plan as required by the Flood Risk Regulations.

The Drain London project provides quarterly meetings with London Councils and key stakeholders to consider flood risk issues, plans and projects across the capital and to seek to find ways for them to work together to minimise and mitigate flood risk.

7 Canal and River Trust

The Canal and River Trust, own the canals in Westminster and it is the responsibility of the Canals and River Trust to ensure that no flooding occurs from canal networks.

8 Network Rail

Network Rail is responsible for the mainline stations in Westminster (Charing Cross, Victoria, Paddington ???) . They manage the entire track including, cuttings, culverts, and tunnels which can be essential to manage flood risk. They are not a RMA but have a responsibility for ensuring that their assets are maintained and do not increase flood risk.

9 Neighbouring Councils

All of Westminster’s neighbouring boroughs are LLFAs. It is essential that we work in partnership with our neighbours to ensure a catchment based approach to manage flood risk. Westminster works with the North Central London Flood Risk group to ensure a catchment approach.

Summary of Responsibilities

Responsibility Stakeholder Action TimelineIncrease understanding of flood risk

WCCWCC/EA

Flood investigation reportsPublish flood risk management plan

2015-2021

June 2015Fund and deliver flood mitigation schemes

WCC/TRFCC Seek funding to prepare Environment Agency Project Appraisal Report for schemes submitted for inclusion in the

Sept 2015

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Thames Regional Flood and Coastal Committee Medium Term Plan for RFCC and Grant in Aid Capital Funding.Engage with businesses and residents on potential flood risk management schemesContribute to and seek partnership funding for flood mitigation schemes.

2015-2021

Asset Register All asset owners

Register and publish flood risk asset list.Inspect, maintain and repair own assets.Maintain and improve flood asset register

2015-2021

Report and Respond to flood incidents

All stakeholders

Police, fire bridgade, ambulance services, EA, WCC, NHS, Thames Water , Canals and River TrustWCC

Flood incident reporting, investigating and recording,

Attend Silver and Gold meetings

Prepare, and implement a Multiagency flood plan

2015-2021

Take account of flood risk through planning

WCC/developers

Develop Planning policy to manage flood risk in Westminster.Refresh Strategic Flood Risk Assessment to inform flood risk assessments.Ensure all new Major Applications have a sustainable drainage management plan agreed by the Lead Local Flood Authority and take account of this as a material consideration in making planning decisions.

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