Land Use Vulnerability Guidance

Transcription

1 Land Use Vulnerability Guidance 0

2 Land Use Vulnerability Guidance Contents 1 Summary Background Most vulnerable Uses Most Vulnerable uses and the risk framework Highly Vulnerable Uses Highly Vulnerable uses and the risk framework Less Vulnerable Uses Less Vulnerable uses and the risk framework Essential Infrastructure Essential Infrastructure and the risk framework Water Compatible Uses Water Compatible uses and the risk framework... 8 Appendix Components of the Definition of Flood Risk Table Matrix of Flood Risk Table SEPA Land Use Vulnerability Classification Appendix Development behind Flood Defences in Built up Areas. Version 1.0. July

3 Land Use Vulnerability Guidance 1.0 Summary 1.1 This guidance provides a framework to assist the assessment of the vulnerability of different types of land use to the impact of flooding. A classification of the relative vulnerability of land uses has been devised which groups a range of land uses into five categories (from most vulnerable uses to water compatible uses). Guidelines for planning responses for each set of land uses are provided, based on the risk framework in Scottish Planning Policy (SPP). 1.2 The land use vulnerability classification differentiates between a range of land uses by generally taking account of flooding impacts on land uses in terms of their relative susceptibility and resilience to flooding and any wider community impacts caused by their damage or loss. A fuller explanation of the use of the term vulnerability for the purposes of land use planning, and its use in the National Flood Risk Assessment, is provided in appendix The guidance is intended to assist the consideration of the flood risk element of vulnerability in the provision of SEPA advice to planning authorities. The guidance was developed through SEPA s Flood Risk and Land Use Planning Working Group which includes representatives from the Built Environment and Environment Divisions of the Scottish Government and the Heads of Planning Scotland. 1.4 It is intended that the land use vulnerability guidance will be of use in the risk assessment of land allocations in development plans and for development management purposes, including where a change of use may increase vulnerability to flood risk by imposing greater impacts than the previous use. The vulnerability classification is for general guidance and for consideration alongside the SPP risk framework. It will primarily be used to provide advisory comment to planning authorities and as such will be most appropriate at the main issues stage of development plans and for pre-application engagement on planning applications. 1.5 It is intended to review the operation of this approach in six months and take account of feedback within SEPA and from external partners. Within this period, it is not intended that the guidance document itself should be used specifically to support any formal objection by SEPA to a planning consultation, although the principles within it will of course continue to be considered on a site by site basis as they always have done. 2.0 Background 2.1 To facilitate the consideration of vulnerability in land use planning, SEPA has developed a classification of land use vulnerability. This has been adapted from the vulnerability classification within Planning Policy Statement 25 (included as Technical Guidance to National Planning Policy Framework, Communities and Local Government, March 2012) and takes cognisance of the classification of impacts on community services undertaken as part of the National Flood Risk Assessment. 2

4 2.2 The classification of land use vulnerability recognises that certain types of development and the people who use and live in them are more at risk from flooding than others. It focuses attention on the relative vulnerability of different developments for their users and the need to avoid potential adverse impacts (e.g. children, the elderly and people with mobility problems may have more difficulty in escaping fast flowing water). 2.3 The land use vulnerability classification comprises five broad categories: 1. Most Vulnerable 2. Highly Vulnerable 3. Less Vulnerable 4. Essential Infrastructure 5. Water Compatible Development (see Table 2). 2.4 The classification has been linked to the risk framework of Scottish Planning Policy by a matrix of flood risk. The matrix provides a general indication of appropriate planning responses within the three flood risk categories of the risk framework for each vulnerability category (see Table 1). This represents a refinement of the range of uses identified in the risk framework. This is intended to assist the interpretation of the risk framework and the determination of appropriate planning responses in line with Flood Risk Management Act duties and SPP principles. 2.5 It should be noted that: Flood risk management infrastructure and other risk mitigation actions, needed to ensure development is safe, may differ between uses within a particular category. The impact of a flood on the particular uses identified within the classification may vary within each category. In particular, a change of use to a dwelling house from other uses within the Highly Vulnerable category could significantly increase the overall flood risk, especially in relation to human health and financial impacts. Any proposal for a change of use to a dwelling house should, therefore, be supported by a flood risk assessment. The list of uses is not definitive. Access and egress arrangements may have a bearing on the vulnerability of land use (including utility services) and the appropriateness of development proposals. The SEPA Interim Position Statement on Planning and Flooding indicates that the land use planning function of local authorities should have a close working relationship with their flood prevention, roads, building standards and emergency planning functions in relation to emergency access and egress. SEPA, therefore, does not comment on access and egress for emergency vehicles. However, it will provide comment on the potential for people to reach safe ground by foot from a particular building or site. 2.6 In summary, the objectives of introducing the land use vulnerability classification are: 3

5 to facilitate consideration of the impacts of flooding in land use planning; to focus attention on the relative vulnerability of different developments for their users. to assist interpretation of the risk framework. The following sections provide an overview of each vulnerability category and its relationship to the SPP risk framework in the matrix of flood risk. This information is summarised in Tables 1 and Most Vulnerable Uses 3.1 The following uses comprise the Most Vulnerable category; police stations, ambulance stations, fire stations, command centres and telecommunications installations required to be operational during flooding; emergency dispersal points; hospitals; basement dwellings; single dwelling houses in remote rural locations; dwelling houses situated behind informal embankments 1 ; caravans, mobile homes and park homes intended for permanent residential use; holiday caravan and camping sites; residential institutions such as residential care homes/ prisons; nurseries, children s homes and educational establishments. Installations requiring hazardous substance consent are included, but where there is demonstrable need to locate such installation for bulk storage of materials with port or other similar facilities, or with energy infrastructure, that require a coastal or water-side location, or other high flood risk areas, then the facilities should be classified as Essential Infrastructure. 3.2 Most vulnerable uses and the risk framework a) Low to medium risk area (0.1% - 0.5% annual probability (AP)). SPP states that essential civil infrastructure (identified within the low to medium flood risk area as hospitals, fire stations, emergency depots etc) is considered generally not suitable in such areas. SPP also indicates that whilst these areas will be suitable for most other development, flood risk assessment may be required at the upper end of the probability range or where the nature of development or local circumstances indicate heightened risk. The matrix of flood risk (Table 1) indicates that for the Most Vulnerable uses, constituting essential civil infrastructure, development is generally not suitable in the low to medium risk area. For other uses in the Most Vulnerable class, flood risk assessment may be required, given that the nature of these more vulnerable uses indicates heightened risk. b) Medium to high risk area (> 0.5% AP) / built up area. SPP states that essential civil infrastructure (identified within the medium to high flood risk area as hospitals, fire stations, emergency depots etc, schools, care homes, ground based electrical and telecommunications equipment) is considered generally not suitable unless subject to an appropriate long term flood risk management strategy. Land raising may 1 Embankments not formally constituted under flood prevention legislation including agricultural flood embankments constructed under permitted development rights. 4

6 also be acceptable, provided suitable compensatory storage can be provided. In addition to the uses classed as essential infrastructure in the risk framework, the Most Vulnerable use category includes a range of uses from basement dwellings to installations requiring hazardous substance consent. The matrix of flood risk (Table 1) recommends that these uses should also be considered as generally not suitable, unless subject to an appropriate long term flood risk management strategy. The term flood risk management strategy is not defined in the SPP. Such a strategy might be expected to take account of climate change uncertainties, hazard and impact scenarios tested to year time horizons and to incorporate structural and non-structural measures. It is assumed therefore that any flood risk management strategy would require a higher level of protection than a standard flood protection scheme 2. c) Medium to high risk area (> 0.5% AP) / undeveloped and sparsely developed. SPP indicates these areas are generally not suitable for additional development subject to a number of limited exceptions. None of the exceptions listed in the risk framework relates to Most Vulnerable uses. The matrix of flood risk (Table 1) therefore incorporates the stipulation, generally not suitable. 4.0 Highly Vulnerable Uses 4.1 The Highly Vulnerable uses comprise dwelling houses, social service homes and hostels (ambulant/adult), student residencies and hotels, non-residential health service uses, landfill and sites for waste management facilities for hazardous waste. 4.2 Highly vulnerable uses and the risk framework a) Low to medium risk area (0.1% - 0.5% AP). SPP indicates that these areas will be suitable for most development other than essential civil infrastructure. Flood risk assessment may be required at the upper end of the probability range or where the nature of development or local circumstances indicate heightened risk. The matrix of flood risk (Table 1) indicates that flood risk assessment may be required for Highly Vulnerable uses, given that the nature of such development indicates heightened risk. 2 Appropriate standard for flood protection schemes, in relation to development, is 0.5% AP, taking into account climate change combined with the ability to be raised in future. 5

7 b) Medium to high risk area (> 0.5% AP) / built up area SPP indicates that within the built up area residential, institutional, commercial and industrial development may be suitable provided flood prevention measures to the appropriate standard 2 exist, are under construction or are planned as part of a long term development strategy. Land raising may also be acceptable provided suitable compensatory storage can be provided. The matrix of flood risk (Table 1) incorporates the above provisions for residential and institutional uses in the Highly Vulnerable use category. Further information on development behind flood defences is provided in Appendix 2. Particular note should be taken of the vulnerability implications of development behind flood defences for any proposed introduction of landfill and sites for waste management facilities for hazardous waste. c) Medium to high risk area (> 0.5% AP) / undeveloped and sparsely developed. SPP indicates these areas are generally not suitable for additional development, subject to a number of limited exceptions. None of the exceptions listed in the risk framework relates to Highly Vulnerable uses. The Matrix of Flood Risk (Table 1) therefore incorporates the stipulation, generally not suitable. 5.0 Less Vulnerable Uses 5.1 Less Vulnerable uses comprise: shops, financial profession and other services restaurants etc, offices, general industry and storage and distribution, nonresidential institutions (not included in higher vulnerable classes), assembly and leisure, agriculture and forestry, waste treatment (except landfill and hazardous waste facilities) minerals working and processing (except sand and gravel). 5.2 Less vulnerable uses and the risk framework a) Low to medium risk area (0.1% - 0.5% AP). SPP indicates that these areas will be suitable for most development other than essential civil infrastructure. Flood risk assessment may be required at the upper end of the probability range or where the nature of development or local circumstances indicate heightened risk. The matrix of flood risk (Table 1) indicates that Less Vulnerable uses may generally be suitable in low to medium risk areas. b) Medium to high risk area (> 0.5% AP) / built up area SPP indicates that within the built up area residential, institutional, commercial and industrial development may be suitable provided flood prevention measures to the appropriate standard 2 exist, are under construction or are planned as part of a long term development strategy. 6

8 Land raising may also be acceptable provided suitable compensatory storage can be provided. The matrix of flood risk (Table 1) incorporates the above mitigation requirements for Less Vulnerable uses. Further information on development behind flood defences is provided in Appendix 2. c) Medium to high risk area (> 0.5% AP) / undeveloped and sparsely developed. SPP indicates these areas are generally not suitable for additional development. Exceptions may arise if the location is essential for operational reasons. The matrix of flood risk (Table 1) indicates that certain Less Vulnerable uses might be considered under these exceptions e.g. where uses relate to navigation, agriculture and transport. 6.0 Essential Infrastructure 6.1 Essential Infrastructure uses comprises essential transport infrastructure and essential utility infrastructure which may have to be located in a flood risk area for operational reasons. This includes electricity generating stations, power stations and grid and primary sub-stations, water treatment works and sewage treatment works and wind turbines. 6.2 Essential infrastructure and the risk framework a) Low to medium risk area (0.1% - 0.5% AP). Uses within the Essential Infrastructure category are not included within the risk framework s list of essential civil infrastructure in the low to medium flood risk area (i.e. hospitals, fire stations, emergency depots etc). SPP indicates that whilst these areas will be suitable for most other development, flood risk assessment may be required at the upper end of the probability range or where the nature of development or local circumstances indicate heightened risk. The matrix of flood risk (Table 1) indicates that the requirement for flood risk assessment may apply to proposed development for Essential Infrastructure, particularly given the need to maintain operational capability. b) Medium to high risk area (> 0.5% AP) / built up area SPP indicates that ground based electrical and telecommunications equipment is considered generally not suitable within the medium to high risk area unless subject to an appropriate long term flood risk management strategy (see section 3.2 (b), above). Land raising may also be acceptable, provided suitable compensatory storage can be provided. The matrix of flood risk (Table 1) incorporates the above considerations for ground based electrical and telecommunications equipment. For transport and other utility infrastructure, the requirement in the risk 7

9 framework for flood risk assessment would apply to ensure operational capability. c) Medium to high risk area (> 0.5% AP) / undeveloped and sparsely developed. SPP indicates these areas are generally not suitable for additional development. Exceptions may arise if a location is essential for operational reasons for transport and some utilities infrastructure where an alternative lower risk location is not achievable. Such infrastructure should be designed and constructed to remain operational during floods. The matrix of flood risk (Table 1) indicates that the above requirements should guide the consideration of uses in the Essential Infrastructure category. 7.0 Water Compatible Uses 7.1 Water Compatible uses comprise infrastructure such as flood control infrastructure, water transmission infrastructure and pumping stations, sewage transmission infrastructure and pumping stations; activities such as sand and gravel workings; docks, marinas and wharves; navigation facilities; MOD defence installations; ship building, repairing and dismantling, dockside fish processing and refrigeration and compatible activities requiring a waterside location; water based recreation (excluding sleeping accommodation); lifeguard and coastguard stations; amenity open space, nature conservation and biodiversity; outdoor sports and recreation (including essential facilities such as changing rooms); essential ancillary sleeping or residential accommodation for staff required by uses in this category, subject to a specific operational warning and evacuation plan. 7.2 Water compatible uses and the risk framework 7.3 Advice in the SPP risk framework on these activities is limited. The nature of the above activities necessitates locations which are prone to flooding. Generally, it is difficult to recommend a specific annual return period to guide development decisions for such uses. SEPA would recommend that the risk of flooding should be assessed giving particular consideration to: 1. Specific locational requirements of the development and availability of alternative locations. 2. Consideration of any loss of floodplain storage (in riverside developments) that may increase flood risk to nearby existing development and options to mitigate against this. 3. Appropriate mitigation measures, including water resistance and resilience measures. 4. Health and safety implications and the need for access, egress and evacuation with specific consideration of, and provision of, measures to provide for these where: The development will attract the public especially vulnerable people such as children and old people. Large numbers of the public may gather and where evacuation routes are limited. Hazardous materials are stored or processed. 8

10 a) Low to medium risk area (0.1% - 0.5% AP) SPP indicates that these areas will be suitable for most development, other than essential civil infrastructure. Flood risk assessment may be required at the upper end of the probability range or where the nature of development or local circumstances indicate heightened risk. The matrix of flood risk (Table 1) generally indicates that Water Compatible uses may be suitable in low to medium flood risk areas. The locational requirements of water compatible developments mean that demands for such uses are unlikely to arise in low to medium flood risk areas. b) Medium to high risk area (> 0.5% AP) / built up area SPP indicates that within the built up area residential, institutional, commercial and industrial development may be suitable provided flood prevention measures to the appropriate standard 2 exist, are under construction or are planned as part of a long term development strategy. The guidance in the risk framework is not specific on Water Compatible uses. The matrix of flood risk (Table I) indicates Water Compatible uses may generally be suitable in medium to high risk flood areas. This would be subject to the considerations outlined in section 7.2, above. c) Medium to high risk area (> 0.5% AP) / undeveloped and sparsely developed. SPP indicates these areas are generally not suitable for additional development. Exceptions may arise if a location is essential for certain operational reasons. The matrix of flood risk (Table 1) indicates consideration may be given to Water Compatible uses related to recreation and amenity uses, provided adequate evacuation procedures are in place; certain utilities infrastructure, designed and constructed to remain operational during floods; and job related accommodation. This would be subject to the considerations outlined in section 7.2, above. 1 Embankments not formally constituted under flood prevention legislation including agricultural flood embankments constructed under permitted development rights 2 Appropriate standard for flood protection schemes, in relation to development, is 0.5% AP, taking into account climate change combined with the ability to be raised in future. 9

11 Appendix 1: Components of the Definition of Flood Risk Probability: = Likelihood of Flood Hazard Hazard = extent, depth, velocity, debris X Flood Risk Consequences: = Impacts due to Receptor Characteristics Characteristics = vulnerability, exposure, value NB: Vulnerability is a function of resilience and susceptibility. The Flood Risk Management (Scotland) Act 2009 places a duty on SEPA and responsible authorities to exercise flood related functions to reduce the overall risk of flooding and promote sustainable flood risk management. It has clarified the definition of flood risk and recognises the need to address all sources of flooding and their impacts. The National Flood Risk Assessment (NFRA) has assessed the likelihood of flooding and its impacts in terms of potential adverse consequences/ impacts on human health, economic activity, the environment and cultural heritage. Impacts have taken into account the number and, where appropriate, the value and vulnerability of the receptors affected. The NFRA divides vulnerability into two components: susceptibility and resilience. Susceptibility is the propensity of a receptor to suffer harm from flooding. For instance, the elderly, frail or sick can be more susceptible to injuries or loss of life. Resilience is the ability of a receptor to recover from damage incurred as a result of flooding. For instance, properties can be designed to be more resilient to flooding through the use of water resilient materials. The use of the term vulnerability for the purposes of the land use planning classification differs slightly from its use in the NFRA. The term land use vulnerability in this guidance is used to differentiate between a range of land uses, generally taking account of flooding impacts on land uses in terms of their relative susceptibility and resilience to flooding. It also reflects wider community impacts caused by their damage or loss. For example, a police station is not more likely to suffer damage (be susceptible) or less able to recover (be resilient) than a comparable office building. However, it is placed in a more vulnerable category than an office use because a higher value is placed on the wider community impacts which would be caused by its potential loss or damage during a flood event. Similar considerations apply to the inclusion of hazardous waste facilities within the highly vulnerable category and other waste treatment facilities being within the less vulnerable category. 10

12 Table 1 - Matrix of Flood Risk - SPP Flood Risk Framework and land Use Vulnerability Classification (*see appendix ) Flood Risk Most Vulnerable Uses Highly Vulnerable Uses Less Vulnerable Uses Essential Infrastructure Water Compatible Uses Little to No risk (>0.1% AP) No constraints. No constraints. No constraints. No constraints. No constraints. Low to Medium risk (0.1% - 0.5% AP) Generally not suitable for essential civil infrastructure. For other uses, FRA may be required at upper end of probability/ or where development or local circumstances indicate heightened risk FRA may be required at upper end of the probability or where the development or local circumstances indicate heightened risk. May be suitable. FRA may be required at the upper end of the probability or where the development or local circumstances indicate heightened risk. May be suitable. Medium to High risk within built up area (>0.5% AP) Generally not suitable for development unless subject to appropriate long term flood risk management strategy. Land raising may be acceptable. Provided flood prevention measures to appropriate standard exist or are planned, may be suitable for residential/ institutional uses. Land raising may be acceptable. Provided flood prevention measures to appropriate standard exist or are planned, may be suitable for commercial/ industrial uses. Land raising may be acceptable. Generally not suitable for ground based electrical and telecom equipment unless subject to a long term flood risk management strategy. FRA for other utilities. Land raising may be acceptable. May be suitable. Medium to high Risk within undeveloped and sparsely developed area (>0.5% AP) Generally not suitable for additional development. Generally not suitable for additional development.. Generally not suitable for additional development. Exceptions may arise for operational reasons e.g. navigation, agriculture and transport. Generally not suitable for ground based electrical/ telecom equipment unless subject to a long term flood risk management strategy; some utilities infrastructure designed and constructed to remain operational during floods may be acceptable. May be suitable for certain recreation/ amenity uses provided adequate evacuation procedures in place; certain utilities infrastructure; job related accommodation

13 Table 2 - SEPA Land Use Vulnerability Classification Most Vulnerable Uses Highly Vulnerable Uses Less Vulnerable Uses Essential infrastructure Police stations, Ambulance stations and Fire stations and Command Centres and telecommunications installations required to be operational during flooding. Emergency dispersal points. Hospitals. Basement dwellings Isolated dwelling houses in sparsely populated locations. Dwelling houses situated behind informal embankments* Residential institutions such as residential care homes/ prisons. Nurseries, children s homes and educational establishments. Caravans, mobile homes and park homes intended for permanent residential use. Sites used for holiday or short-let caravans and camping. Installations requiring hazardous substance consent.(where there is demonstrable need to locate such installation for bulk storage of materials with port or other similar facilities, or with energy infrastructure, that require a coastal or water-side location, or other high flood risk areas, then the facilities should be classified as essential infrastructure.) Buildings used for dwelling houses. Social services homes (ambulant /adult) and hostels; student halls of residence; and hotels. Non-residential uses for health service. Landfill and sites used for waste management facilities for hazardous waste. Buildings used for: shops; financial, professional and other services; restaurants and cafes; hot food takeaways; drinking establishments; nightclubs; offices; general industry; storage and distribution; non-residential institutions not included in most and highly vulnerable classes ; and assembly and leisure. Land and buildings used for agriculture and forestry which are subject to planning control. Waste treatment (except landfill and hazardous waste facilities) Minerals working and processing (except for sand and gravel working). Essential transport infrastructure (including mass evacuation routes) which has to cross the area at risk. Essential utility infrastructure which has to be located in a flood risk area for operational reasons, including electricity

14 generating power stations and grid and primary sub-stations; sewage treatment plants and water treatment works. Wind turbines. Water Compatible Uses Flood control infrastructure. Water transmission infrastructure and pumping stations. Sewage transmission infrastructure and pumping stations. Sand and gravel workings. Docks, marinas and wharves. Navigation facilities. MOD defence installations. Ship building, repairing and dismantling, dockside fish processing and refrigeration and compatible activities requiring a waterside location. Water based recreation (excluding sleeping accommodation). Lifeguard and coastguard stations. Amenity open space, nature conservation and biodiversity; outdoor sports and recreation and essential facilities such as changing rooms. Essential ancillary sleeping or residential accommodation for staff required by uses in this category, subject to a specific warning** and evacuation plan. Footnotes *Embankments not formally constituted under flood prevention legislation including agricultural flood embankments constructed under permitted development rights ** In this context, specific warning does not mean a formal flood warning from SEPA. SEPA does not support the provision of flood warning as a viable reason to develop in flood risk areas. Warning is a non-structural measure which does not physically prevent flooding and has associated uncertainties. The classification is adapted from the Defra/ Environment Agency research on Flood Risks to People (FD2321/TR2) and Planning Policy Statement 25 (included as Technical Guidance to National Planning Policy Framework, Communities and Local Government, March 2012); account has also been taken of the NFRA;s classification of disruptive impacts on community services. It is also based on the need of some uses to keep functioning during flooding

15 When using the above table, developments that combine a mixture of uses should be placed in the higher of the relevant classes of flood risk vulnerability. It should be noted that the impact of a flood on the particular land use could vary within each vulnerability class. In particular, a change of use to a dwelling house within the Highly Vulnerable category could significantly increase the overall flood risk, especially in relation to human health and financial impacts. Any proposal for a change of use to a dwelling house should, therefore, be supported by a flood risk assessment. The redevelopment and/or change of use of a site provides a valuable opportunity to reduce the vulnerability of that site to flooding and therefore to reduce overall flood risk. This can be achieved through changes to less vulnerable land uses and improvements to the management of flood risk on the site

16 Appendix 2 Development behind Flood Defences in Built Up Areas Within built up areas, the SPP risk framework indicates that medium to high risk areas may be suitable for residential, institutional, commercial and industrial uses provided flood prevention measures to the appropriate standard already exist or are planned as part of a long term development strategy. In the allocation of any sites in medium to high risk areas, preference should be given to areas already defended to required standards 1. A development which requires additional flood protection measures will normally only be acceptable outside or adjoining the boundary of medium to high risk areas (see page 43, para 206, SPP). While SPP indicates that in areas protected by existing flood protection measures, brownfield development will generally be acceptable, defences require to be adequate and properly maintained. It further cautions that although flood protection measures can reduce the probability of flooding, they cannot eliminate it entirely. It should also be noted that the differences between the build date (and design life) of a formal scheme and that of a proposed development (e.g. housing scheme), may create a period of time for which the standard of protection is either diminished or lost. 1 Appropriate standard for flood protection schemes, in relation to development, is 0.5% AP, taking into account climate change, combined with the ability to be raised in future. 15

17