Flood Risk & Surface Water Management. Page 1 of 20

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1 Page 1 of 20 Flood Risk & Surface Water Management

2 Flood Risk & Surface Water Management and the Planning Process Introduction The purpose of this document is to increase awareness of the potential of flood risk and water management as key considerations in the assessment of proposals for new development. In advance of the Core Strategy being adopted and the SuDs Approving Body (SAB) coming into effect, this document provides guidance to applicants on when to submit a flood risk assessment, what factors should be addressed in the submission of a flood risk assessment and how the Council will respond. Developers are advised to consider the advice provided in this document before proceeding with applications for planning permission. The Council also offers a preapplication advice service where flood risk and surface water management related to specific sites can be considered in more detail prior to final submission. Page 2 of 20

3 Background Under the Flood Risk Regulations (2009), the Council is designated as the Lead Local Flood Authority (LLFA) for Newcastle and works in partnership with key agencies to manage flood risk in the city. Within the Council, this responsibility currently falls to the Flood Management Team within Technical Services. Following widespread flooding across the UK in summer 2007, the Pitt Review identified a need for surface water runoff to be properly managed and included amongst its 92 recommendations that the automatic right to connect surface water drainage of new developments to the sewerage system should be removed and that government should identify who is responsible for the ownership and management of sustainable drainage systems. The Flood and Water Management Act (2010) changed the way that surface water and flood risk are managed in the UK, the biggest change being that the responsibility for flooding in the UK no longer lies entirely with the Environment Agency. The Act subsequently gave LLFAs responsibility for managing the risk of flooding from surface water. As part of the Flood and Water Management Act, these LLFA s will also become responsible for adopting Sustainable Drainage Systems (SuDS) by forming a SuDS Approval Body (SAB). The SAB will be responsible for appraisal, approval, adoption and maintenance of sustainable drainage systems in new development and redevelopment before construction can commence. Developers will be required to submit either joint or separate applications to the Council to approve their Sustainable Drainage System. This is due to come into effect in October 2014.The Environment Agency remains responsible for managing flood risk related only to main rivers and the sea. Until then it is still important to involve the LLFA on relevant planning proposals to ensure that drainage and flooding issues are taken into account by developers and assessed by Officers, not only in respect to site specific flooding, but to ensure that flood risk elsewhere does not increase as a result of the proposals. This will ensure that new development is designed to be in accordance with the Core Strategy and Unitary Development Plan (UDP) policy. Page 3 of 20

4 Key Agencies The key agencies that need to work in partnership to manage flood risk are as follows: The Environment Agency (EA) has a strategic overview for all flood and coastal erosion risk management activities, as well as specific responsibility for managing the risk of flooding from main rivers and the sea. In Newcastle, the main rivers are the Tyne and the Ouseburn. The EA also produces maps showing the risk of flooding from surface water, rivers or the sea and issues flood warnings. Flood Zones Mapping - Northumbrian Water is responsible for maintaining the public sewerage network, and managing the risk of flooding from that system. Local Planning Authority - Planning Policy, who are responsible for the production, monitoring and updating of the Council s Strategic Flood Risk Assessment and Development Management both have a role in local flood risk management, avoiding development in flood risk areas where possible (or, where necessary, making it safe through mitigation measures and managing residual risk) and ensuring new development will not increase flood risk elsewhere. Page 4 of 20

5 Legislation European Union (EU) Context The Water Framework Directive The Water Framework Directive 2000/60/EC (WFD) is EU legislation that came into force in December 2000 and was enacted into UK law in December The legislation requires member states to make plans to protect and improve the water environment. It applies to all surface freshwater bodies, including lakes, streams, rivers and canals; transitional bodies such as estuaries; groundwater; and coastal waters out to one mile from low water. There are four main aims of the WFD which are to: improve and protect inland and coastal waters promote sustainable use of water as a natural resource create better habitats for wildlife that lives in and around water create a better quality of life for everyone The Directive requires European Union member states to: prevent deterioration in the status of aquatic ecosystems, protect them and improve the ecological condition of waters; aim to achieve at least good ecological status for all water bodies by If a water body has good ecological status it means that it has biological, chemical and structural characteristics similar to those expected under nearly undisturbed conditions. Where it is not possible to achieve this by 2015, and subject to criteria set out in the directive, aim to achieve good ecological status by 2021 or 2027; meet the requirements of the Water Framework Directive Protected Areas; promote sustainable use of water as a natural resource; conserve habitats and species that depend directly on water; progressively reduce or phase out the release of individual pollutants or groups of pollutants that present a significant threat to the aquatic environment; progressively reduce the pollution of groundwater and prevent or limit the entry of pollutants; contribute to mitigating the effects of floods or droughts. River Basin Management Plans produced by the Environment Agency detail the pressures facing the water environment and what actions need to be taken in order for the WFD to be met in each area. Page 5 of 20

6 National context Flood and Water Management Act 2010 The Flood and Water Management Act (FWMA) places the responsibility for coordinating local flood risk management on the county or unitary authority, making them a Lead Local Flood Authority (LLFA). In this context, the Act uses the term local flood risk to mean flood risk from: surface runoff groundwater and ordinary watercourses Planning Policy and Guidance National Planning Policy Framework The NPPF states that account should be taken to flooding in the assessment of planning applications. Inappropriate development in areas at risk of flooding should be avoided by directing development away from areas at highest risk, but where development is necessary, making it safe without increasing flood risk elsewhere. The NPPF states that when determining planning applications, local planning authorities should ensure flood risk is not increased elsewhere and only consider development appropriate in areas at risk of flooding where it can be demonstrated that within the site the most vulnerable development is located in areas of lowest flood risk and development is appropriately flood resilient and resistant and it gives priority to the use of sustainable drainage systems. A Flood Risk Assessment should identify and assess the risks of all forms of flooding to and from the development. It should also demonstrate how these flood risks will be managed so that development remains safe throughout its lifetime taking climate change into account. Practice Guidance for the National Planning Policy Framework The NPPF Practice Guidance also includes further details on: Sequential and Exemption tests, flood risk vulnerability categories, climate change allowances, and flood resilience and resistance guidance. Local Planning Policy The City Council s local planning policy officially known as the Local Development Framework includes the following policies related to flood risks and surface water management. Page 6 of 20

7 Planning for the Future - Core Strategy and Urban Core Plan The Council s submission draft Core Strategy and Urban Core Plan has been submitted to the Secretary of State with the examination in public scheduled for June In accordance with paragraph 216 of the NPPF, weight can be given to relevant emerging policies according to the stage of preparation of the emerging plan, the extent of unresolved objections to polices and the degree of consistency with the NPPF. Within the Core Strategy Policy CS17 is relevant to the assessment of flood risk and water management The policy seeks to ensure that new development integrates a set of measures to reduce flood risk, avoids an adverse impact on water quality and quantity and provides opportunities to enhance biodiversity Policy CS17: Flood Risk and Water Management Development will avoid and manage flood risk from all sources, taking into account the impact of climate change over its lifetime. Development will: 1. Avoid and manage flood risk to people and property by: i. Locating new development in areas with the lowest risk ii. Managing flood risk from development to ensure that the risk is not increased on site and/or elsewhere iii. Ensuring opportunities are taken for development to contribute to the mitigation of flooding elsewhere are taken iv. Prioritise the use of Sustainable Drainage Systems, given the multifunctional benefits to water quality, green space and habitat enhancement. v. Ensuring development is in accordance with the Council s Strategic Flood Risk Assessment vi. Requiring a Flood Risk Assessment for sites over 0.5ha in Critical Drainage Areas as identified in the Council's Strategic Flood Risk Assessment 2. Ensure water supply and foul and surface water infrastructure is provided with adequate capacity. 3. Not adversely affect water quality and where possible seek to improve water quality (See Water Framework Directive). 4. Control, separate and minimise surface water runoff, discharging in order of priority to: i. infiltration based Sustainable Drainage Systems; ii. a watercourse; iii. a surface water sewer; iv. a combined sewer Page 7 of 20

8 More specific policy requirements for individual allocated development sites are set out in the Core Strategy Chapter on Sub-Areas and Site Specific Policies. Newcastle Saved Unitary Development Plan (UDP) Policies POL14 Development which would be at direct risk of flooding or likely to increase the risk of flooding elsewhere will not be allowed. The City Council wishes to ensure that new development will not increase the risk of flooding which could endanger life or damage property. Development may increase the risk of surface water run off, adding to the flood risk downstream, and may increase the risk of pollution and damage to river habitats. Page 8 of 20

9 Flood risk and surface water management The Council recognises that one of the greatest challenges for managing flood risk and surface water management is the legacy of drainage networks that struggle to cope with the increase in surface water volumes due to increased urbanisation and climate change. The proper consideration of surface water runoff as part of all development, and the use of sustainable drainage systems (SuDS), is key to the successful management of both existing and future flood risk. Flood Risk Assessments and Drainage Strategy When considering planning applications, Local Planning Authorities should ensure that the development itself is not at risk of flooding, and flood risk is not increased elsewhere. A developer will need to submit a Flood Risk Assessment and a drainage strategy to the Local Planning Authority alongside a planning application. The Local Planning Authority is the lead organisation for determining whether proposals comply with the Council's planning polices and will consult with the LLFA, NWL and the EA. The completion of a flood risk assessment is no longer limited to consultation with the EA. Instead FRA's must be written in accordance with National Planning Policy Framework and other guidance, such as the British Standard for assessing flood risk in development (BS8533), introduced in This means that planning application decision are no longer based solely on flood risk from, and to main rivers, but also on flood risk related to surface water (pluvial) sources, groundwater and from smaller rivers (ordinary watercourses). In addition to the EA, the LLFA also needs to be consulted as part of the planning process, as they are a key consultee to the Local Planning Authority. As SABs become operational in approving SuDS designs, the LLFA will become even more key influencing the planning process. When submitting a planning application a site-specific flood risk assessment including drainage details is required in the following circumstances: proposals on sites of 1 hectare or greater proposals of 0.5 hectares or greater in an area of critical drainage problems as identified by the Council s SFRA development within an area which has critical drainage problems (as notified to the local planning authority by the Environment Agency) all proposals for new development (including minor development, household development and change of use) in Flood Zones 2 and 3 where proposed development (or a change of use to a more vulnerable use class) may be subject to other sources of flooding, such as flooding from surface water runoff. This includes applications for prior approval. This should identify and assess the risks of all forms of flooding to and from the development and demonstrate how these flood risks will be managed, taking Page 9 of 20

10 climate change into account and should also include drainage strategy. This will include sequential and exception tests for major developments. Guidance on the sequential approach and the exception test is provided in paragraphs of the NPPF. The FRA should identify opportunities to reduce the probability and consequences of flooding. The FRA should include the design of surface water management systems including Sustainable Drainage Systems (SUDs) and address the requirement for safe access to and from the development in areas at risk of flooding What should a Flood Risk Assessment Include For both residential extensions and non-residential extensions of less than 250sq. metres in a critical drainage area and Flood Risk Zones 2 and 3, a simple flood risk assessment is required using the link below: Otherwise, a Flood Risk Assessment should identify and assess the risks of all forms of flooding to and from the development and demonstrate how these flood risks will be managed, taking climate change into account. A Flood Risk Assessment should include the following information: Development within Flood Zone 1 Existing flood risk to the site from localised sources & impact of development upon run off rates; Design measures proposed to mitigate run off rates (SuDS). Development within Flood Zone 2 Existing flood risk to the site from all sources & potential impact of development upon flood risk only (High level assessment only); Design measures proposed to mitigate risk of flooding, and their impact (details should include floor levels, ground levels, evacuation routes, SuDS). Development within Flood Zone 3 Existing flood risk to the site from all sources (e.g. flood depth, flow routes, flood velocity, defence failure); Potential impact of development upon flood risk; Design measures proposed to mitigate risk of flooding, and their impact (details should include floor levels, ground levels, evacuation routes, SuDS etc). In order to satisfy Core Strategy Policy CS17, applications for new development in Flood Zones 2 and 3 should contain a sequential testing statement (except for householder extensions, non-residential extensions of less than 250sq. metres or renewable energy proposals) which should demonstrate to the local authority that Page 10 of 20

11 there are no reasonably available alternative sites where the proposed development could be sited within an area of lower flood risk. The applicant needs to submit the following evidence to allow the local authority to consider the sequential test: A written statement explaining the area of search; A map identifying all other sites considered within lower areas of flood risk; A written statement explaining why the alternative sites listed within lower areas of flood risk are not reasonably available. However, if the sequential test is passed there are still some vulnerable types of development that should not normally be allowed in Flood Zones 2 and 3 unless there are exceptional circumstances. These circumstances are established by using the Exception test. Please see Practice Guidance to the National Planning Policy Framework to clarify when this test will be required. For the exception test to be passed it has to satisfy each of the following three tests: It must be demonstrated that the proposed development provides significant wider sustainability benefits to the community that outweighs flood risk; The development must be on previously developed land; A Flood Risk Assessment submitted with the application must demonstrate that the development will be safe without increasing flood risk elsewhere and where possible reduce flood risk overall. Environment Agency Advice The Environment Agency is non departmental public body and has responsibilities for protecting and enhancing the environment as a whole (air, land and water) and contributing to the government s aim of achieving sustainable development in England and Wales. The Environment Agency manages flood risk from main rivers, but also has a strategic overview role across all types of flooding. A flood risk consultation matrix is available from the Environment Agency website and has been specifically created to demonstrate in more detail the scenarios for which the Environment Agency has applicable standing advice. This is aimed at Local Authorities but could be of use to developers. For the larger, more complex developments, standing advice is not sufficient and the Environment Agency should be consulted on the development application with an accompanying FRA. For some, generally smaller, development types the city council makes its decision without advice from the Agency. If proposals are discussed with the Council prior to submission of a formal application, we will advise further as to what is required and who will be consulted on a particular case. Page 11 of 20

12 SuDS Guidance Core Strategy Policy CS17 sets the priority for the incorporation of Sustianable Drainage Systems (SuDS) into new developments to manage and minimise surface water. SuDS generally are landscaped facilities such as wetland, retention ponds, soakaways, swales and/or permeable surfaces, the primary function being to reduce the volume and peak rates of water run-off from new development, but they should also fulfil their potential to provide wildlife habitats and amenity spaces. SuDS can also improve water quality by increasing the filtration of pollutants and thereby support the Water Framework Directive. DEFRA are currently in the process of developing National Standards for Sustainable Drainage Systems. These are currently out to consultation and the final version will be published shortly. Once they are adopted, developers will need to ensure that their proposals are in accordance with both the National Standards and the associated local standards. These standards will be used to assess applications submitted once the SAB is in place. In addition to the National Standards, and in advance of their adoption, in order to comply with Core Strategy Policy CS17 and UDP Policy POL14 drainage systems should be designed so that flooding from the system does not occur: 1) On any part of the site for a 1 in 30 year rainfall event with 30% additional allowance for climate change 2) During a 1 in 100 year rainfall event with 30% additional allowance for climate change, in any part of a building (including a basement) or any utility plant susceptible to water (e.g. electricity substation) 3) On neighbouring sites during a 1 in 100 year rainfall event with 30% additional allowance for climate change Flows in excess of the above criteria must be managed in appropriate flood conveyance routes so as to minimise the risk to people and property both on and off the site. Surface water not collected for use must in order of priority be: 1) Discharged into the ground (infiltration) or where not reasonably practicable, 2) Discharged into a surface water body or where not reasonably practicable, 3) Discharged into a surface water sewer, highway drain, or other drainage system, or where not reasonably practicable, 4) Discharged to a combined sewer. As schemes progress down the order of priority, developers will need to provide justification as to why more preferable options are not reasonably practicable. Applicants will also need to provide details of the maintenance arrangements proposed for the drainage system. Page 12 of 20

13 Examples SuDS can provide multiple benefits to a development which as well as helping to reduce flood risk can also improve the amenity value of the development and increase biodiversity. The following table is taken from the SuDS Manual which is available from the CIRIA website ( and provides examples of the methods which can be used to incorporate SuDS into a new scheme. The list is not exhaustive but provides an indication of the various methods which can be used to reduce the risk of flooding. When designing SuDS it is often advisable that development be designed around existing flows of water. Please also refer to guidance links provided at end of document. Page 13 of 20

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15 Pre-application Advice The Council recognises the importance of sharing expertise and information to be able to deliver effective and timely decisions. Flood risk should be factored into the earliest stages of applications and applicants are advised to consider flood risk in the submission of any pre-application enquiry. In its response to you the Council will provide advice as to the validation requirements for any proposal which will include flood risk assessments and drainage strategies where required. Further advice on the Council s pre-application advice service can be found on the Council website. It is advised that prior to making an application, developers should familiarise themselves with relevant local and national water management policy and guidance. Pre application discussions are strongly encouraged to ensure that all drainage matters are given adequate consideration from the outset. Developers should contact the appropriate organisation for pre-application discussions Northumbrian Water Pre-development enquiries Environment Agency Enquiries Page 15 of 20

16 Assessment of the planning application Consultation As part of any planning application we are required to notify the relevant external and internal bodies to assist in the assessment of any proposal. Where flooding and water management is a potential issue the following bodies will be consulted on receipt of a planning application in the circumstances listed below: We will consult the Environment Agency for: - Development of land 1ha or more - An application for EIA development - Development (other than minor development*) of land within Flood Zone 2 or 3 - Development (other than minor development*) in Flood Zone 1 and with Critical Drainage Problems (EA definition**) - Development involving the carrying out of works or operations in the bed of, or within 20m of the top of a bank of, a main river; or the culverting or control of flow of any river or stream - Where the applicant states they will discharge of surface water to a main river - Applications for prior approval of change of use under Schedule 2 part 1 Class J or M *Minor development in this instance means 1) extensions of a dwellinghouse or alterations within the curtilage of a dwellinghouse for any purpose incidental to the enjoyment of the dwelling 2) the extension of a building used for non-domestic purposes where the floorspace created does not excedd 250 square metres 3) the alteration of an existing building where there is no increase in size. **As of May 2013 the EA has confirmed that within Flood Zone 1 they have not identified and notified the Council of any areas with critical drainage problems. We will consult the Council s Flood Management team for: - Sites within or adjacent to areas at risk of surface water flooding - Sites within or adjacent to areas that have experienced previous flooding incidents - Development sites of 0.5ha or greater in a critical drainage area as defined by the SFRA - Household development within Flood Zones 2 or 3. - Sites within 20 metres of a watercourse (river, stream or beck) or site includes or adjoins a culvert - Where on the planning application form the applicant has stated that they will discharge surface water to: - A sustainable drainage system - A soakaway - To a watercourse such as a pond, lake or river Page 16 of 20

17 We will consult Northumbrian Water where: - Applicants state that surface water will be disposed of to main sewer - Where applicants do not state how surface water is to be disposed of Other bodies We will consult other bodies as deemed appropriate. Examples include English Heritage where flooding may affect a heritage asset or Natural England where flood risk or flood prevention measures may affect a wildlife corridor or other protected area. Making a decision Development will only be considered appropriate in areas at risk of flooding where, informed by a site-specific flood risk assessment following the Sequential Test, and if required the Exception Test, it can be demonstrated that: within the site, the most vulnerable development is located in areas of lowest flood risk unless there are overriding reasons to prefer a different location; and; development is appropriately flood resilient and resistant, including safe access and escape routes where required, and that any residual risk can be safely managed. In order to receive planning approval developers must demonstrate that their development is in accordance with CS17 and POL14. Following the adoption of the National Standards, developers will need to demonstrate compliance with these standards as this will be required in order to obtain SAB approval. Page 17 of 20

18 Additional flooding & water management documents Prelimary Flood Risk Assessment- A high level screening exercise to identify areas where the risk of flooding from surface water, groundwater or ordinary watercourses is significant at a national level. Also reviews historical flood incidents within the Newcastle Area. LLFAs, which are responsible for managing the risk of flooding from local sources (surface water runoff, ordinary watercourses and groundwater). (required under FRR 2009) Strategic Flood Risk Assessment (SFRA) The SFRA comprises relevant data, guidance and recommendations from flood risk issues at a local level. It is a planning tool that enables the LPA to carry out sequential and Exceptions testing and to select and develop sustainable site allocations at lower risk of flooding. It provides guidance on mitigation measures. Newcastle City Council Level 2 Strategic Flood Risk Assessment Volume I : SFRA Report Newcastle City Council Level 2 Strategic Flood Risk Assessment, Volume II, SFRA User Guide Contains suds info at Section G. Sustainable Drainage Systems Sets out description of SUDs / techniques Surface Water Management Plan- Outlines the preferred surface water management strategy. The plan considers flood risk from surface runoff, groundwater and ordinary watercourses and the interaction with flooding from main rivers, the sea and sewers. Provides a greater understanding of local flood risk and to develop action plans to manage the risks. Addresses the impact of new developments on drainage patterns and surface water flood risk but also considers areas with an existing risk of surface water flooding providing guidance on SuDs, NewcastleGateshead Surface Water Management Plan: Surface Water Management Strategy NewcastleGateshead Surface Water Management Plan Identifying Areas at Risk Draft National Standards for SuDS prepared by DEFRA as part of the consultation on the implementation of the SuDS Approving Body. suds-consult-annexa-national-standards pdf Page 18 of 20

19 Newcastle Gateshead Outline Water Cycle Study (2010) -The document assesses potential future growth and development against the capacity of water services infrastructure. (e.g water supply infrastructure, sewerage systems and wastewater treatment plants) to accommodate that growth. It Provides information and assurances that the Council s growth and regeneration aspirations can be supplied with sufficient water supply and wastewater treatment facilities. It seeks to assess the impact of development, at a strategic level, on the water environment and that water services infrastructure either has sufficient capacity or can be provided in a timely manner. Chapter 7 (pg63) privdes guidance for developers. Chater 7 (pg 63 provides guidance for developers. SOutlineReport.pdf Climate Change Risk Assessment and Action Plan - Sets out the Council s overall programme for tackling climate change through a series of action plans around how we plan to deliver carbon emississons reductions from Newcastle and tackle the adaption agenda (section 16, Drainage and Flood Management) Tyne Catchment Flood Management Plan (CFMP) Provides an overview of the flood risk in the Tyne catchment and sets out the EA s preferred plans and actions for sustainable flood risk management over the next 50 to 100 years. The policy for the two catchment units relevant to Newcastle ( Lower Tyne Tidal and Ouseburn ) is option 5: Take further action to reduce the risk of flooding. Page 19 of 20

20 Useful Links The SUDS manual (C697) 2007 This CIRIA guidance provides best practice guidance on the planning, design, construction, operation and maintenance of SuDS. Site handbook for the construction of SUDS (C698) 2007 This CIRIA handbook provides guidance on the construction of SuDS to facilitate their effective delivery. Planning for SuDS making it happen (C687) 2010 This CIRIA guidance Provides an introduction to SuDS and the planning and development process. Retrofitting to manage surface water (C713) 2012 This CIRIA guidance sets out a process to achieve the retrofitting of surface water management measures. It integrates the principles of urban deisgn with surface water management. UK Rain Gardens guide provides gui9dnace to help the homeowner or property manager to create a simple rain garden within their own property. Sustianble Drainage Systems: maxmising the potential for people and wildlife Susdrain is a web-site that provides information and case studies to facilitated the delivery of SuDS Page 20 of 20