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FLOOD RISK SEQUENTIAL TEST Fld Risk Sequential Test Practice Nte August 2013 i

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FLOOD RISK SEQUENTIAL TEST Cntents 1. Intrductin... 1 2. The Sequential Test and Fld Znes... 2 2.1. When is the Sequential Test nt required?... 3 2.2. Carrying ut the Sequential Test... 4 2.2.1. Defining the search area... 4 2.2.2. Identifying alternative sites... 6 2.2.3. Determining whether alternative sites are reasnably available... 6 3. Prpsals that pass the Sequential Test (r d nt require it)... 8 3.1. The Exceptin Test... 8 3.2. Site-specific Fld Risk Assessment... 8 Appendix 1: Surces f infrmatin... 9 Appendix 2: Fld Risk Vulnerability Classificatin... 10 iii

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Bristl Develpment FramewrkPractice Nte (July FLOOD RISK SEQUENTIAL TEST 1. Intrductin Paragraphs 100-104 f the Natinal Planning Plicy Framewrk (NPPF) and plicy BCS16 f the adpted Bristl Cre Strategy (June 2011) set ut a sequential, risk-based apprach t the lcatin f develpment t avid peple and prperty being expsed t the risk f flding and manage any residual risk. An imprtant step in the sequential apprach t fld risk is the applicatin f a Sequential Test t prpsals fr develpment in areas at risk f flding, which examines whether there are alternative sites less at risk f flding that wuld be apprpriate fr the prpsed develpment. If, fllwing the Sequential Test, the cuncil cnsiders that there are n reasnably available sites in areas less at risk f flding that wuld be apprpriate fr the prpsed develpment, then the Sequential Test is passed and it may be apprpriate fr the prpsed develpment t prceed subject t a site-specific fld risk assessment and apprpriate mitigatin measures t ensure that the develpment is made safe fr its lifetime withut increasing fld risk elsewhere. This practice nte explains hw the Sequential Test will be applied thrugh the develpment management prcess in Bristl. It is a pririty f the Bristl Cre Strategy t achieve regeneratin acrss a wide range f areas within the city, and as such the cuncil, while recgnising the imprtance f aviding and managing fld risk, will take a practical and pragmatic apprach t the cnsideratin f alternative sites fr develpment as part f the Sequential Test when cnsidering prpsals fr develpment. 1

FLOOD RISK SEQUENTIAL TEST 2. The Sequential Test and Fld Znes The Sequential Test is undertaken n the basis f the fllwing fld znes, as set ut in Table 1 f the Technical Guidance t the NPPF: Fld zne Assciated fld risk Zne 1 Lw prbability This zne cmprises land assessed as having a less than 1 in 1000 annual prbability f river r sea flding in any year Zne 2 Zne 3a Zne 3b Medium Prbability This zne cmprises land assessed as having between a 1 in 100 and 1 in 1000 annual prbability f river flding r between 1 in 200 and 1 in 1000 annual prbability f sea flding in any year. High prbability This zne cmprises land assessed as having a 1 in 100 r greater prbability f river flding r a 1 in 200 r greater prbability f flding frm the sea in any year. The functinal fldplain This land cmprises land where water has t flw r be stred in times f fld. Fig.1: Summary f fld znes (see Technical Guidance t the NPPF: Table 1) Table 2 f the Technical Guidance t the NPPF grups different develpment types int different vulnerability classificatins, fr example: Offices are defined as less vulnerable Dwelling huses are defined as mre vulnerable Basement dwellings are defined as highly vulnerable Table 2 is reprduced in full at Appendix 2 f this Practice Nte. Fr each fld zne, Table 3 f the Technical Guidance t the NPPF then sets ut whether develpment f the varius different vulnerability classificatins is apprpriate. If s, then the develpment may be able t prceed subject t a Sequential Test and, in sme cases, an Exceptin Test. If develpment within a certain vulnerability classificatin is identified as inapprpriate, then planning permissin will nt generally be permitted. Fig.2: Technical Guidance t the NPPF: Table 3 2

Bristl Develpment FramewrkPractice Nte (July FLOOD RISK SEQUENTIAL TEST Maps f Fld Znes in England are maintained by the Envirnment Agency. In Bristl, hwever, the Sequential Test shuld usually be carried ut with reference t the latest lcal fld risk evidence. The Strategic Fld Risk Assessment fr Bristl (SFRA) and subsequent studies such as the frthcming Central Area Fld Risk Assessment (CAFRA) mdel lcal fld risks in mre detail, taking int accunt fld defences, and prvide further infrmatin in certain areas n the depth and severity f the ptential flding. The lcal fld risk evidence mdels nt just the present day fld risk but als the ptential future fld risk taking accunt f the likely effects f climate change. In Bristl, as required by plicy BCS16 f the Cre Strategy, the future fld risk with climate change shuld be taken int accunt in undertaking the Sequential Test. Cnsequently, the fld znes used fr the Sequential Test in Bristl will be the fld znes with climate change where such data is available. The Sequential Test in Bristl will seek sites in the fllwing rder f preference: 1. Sites in Fld Zne 1 2. Sites in Fld Zne 2 3. Sites in Fld Zne 3a 2.1. When is the Sequential Test nt required? Prpsals fr develpment within either Fld Znes 2, 3a r 3b 1 as existing r Fld Zne 3a with climate change require a Sequential Test unless any f the fllwing apply: The prpsal is fr a change f use f existing building(s) 2. Reasn: As set ut in the Natinal Planning Plicy Framewrk (para.104) and assciated Technical Guidance (para.10). The prpsal is fr a minr extensin r alteratin t an existing building r its assciated structures, defined as: Minr nn-residential extensins: industrial/cmmercial/leisure etc. extensins with a ftprint less than 250m²; Husehlder develpment: e.g. sheds, garages, games rms etc. within the curtilage f the existing dwelling in additin t physical extensins t the existing dwelling itself. This definitin excludes any prpsed develpment that wuld create a separate dwelling within the curtilage f the existing dwelling e.g. subdivisin f huses int flats. Alteratins: develpment that des nt increase the size f buildings e.g. alteratins t external appearance r a replacement bundary treatment. Reasn: As set ut in the Natinal Planning Plicy Framewrk (para.104) and assciated Technical Guidance (para.10). The prpsal is fr the replacement f an existing building 3. Reasn: As set ut in the PPS25 Practice Guide (para.4.40). The replacement f an existing building with a new, suitably fld-resilient design is likely t be preferable 1 Nte that mst types f develpment are nt acceptable in principle in Fld Zne 3b (see Fig.2). 2 This nly applies t prpsals that invlve n extensin t the building (abve and beynd that cnsidered t be a minr extensin r alteratin as set ut abve). 3 This nly applies where there wuld be n increase in the intensity f use f the site, such as the replacement f an existing single dwelling huse. 3

FLOOD RISK SEQUENTIAL TEST t the change f use f an existing building if the expsure f peple r prperty t flding is t be minimised. The prpsal is fr a renewable energy prject (e.g. wind turbines). Reasn: As set ut in the PPS25 Practice Guide (para.4.39). The cuncil has already sequentially tested the site as part f an allcatin fr develpment within the develpment plan (including emerging develpment plan dcuments that have reached the Publicatin stage). 4 Reasn: As set ut in the Natinal Planning Plicy Framewrk (para.104). The prpsal is fr a site with an existing planning permissin (full r utline) fr a cmparable mix and intensity f uses. Reasn: As the principle f develpment has already been decided. If an applicant fr planning permissin believes that their prpsal is exempt frm the need fr a Sequential Test, they shuld justify this clearly as part f their applicatin with reference t the exemptins set ut abve. Prpsals that pass the Sequential Test will als still require a site-specific Fld Risk Assessment (see Develpment that passes the Sequential Test belw). 2.2. Carrying ut the Sequential Test The applicant fr any prpsal nt cvered by ne f the abve exemptins will be expected t assemble the evidence t allw the cuncil t cnsider whether the develpment passes the Sequential Test and submit it as part f their planning applicatin. The Sequential Test shuld demnstrate that there are n reasnably available alternative sites apprpriate fr the prpsed develpment in areas with a lwer prbability f flding. If the applicant can demnstrate this t the cuncil then the Sequential Test is passed. Applicants submitting a Sequential Test shuld include the fllwing infrmatin: A written statement explaining the area f search fr alternative sites; A map r clear schedule identifying all alternative sites cnsidered within areas f lwer fld risk; and A written statement explaining why the alternative sites are nt reasnably available. 2.2.1. Defining the search area As set ut in the PPS25 Practice Guide (paras.4.17-4.18), the area f search fr alternative sites will nrmally be the whle lcal authrity area. Hwever, Bristl cntains a number f areas in need f regeneratin in which it wuld be apprpriate t carry ut the Sequential Test ver a smaller area. Develpment in the fllwing areas will nt be expected t lk fr alternative sites in ther parts f the city as part f the Sequential Test: Bristl City Centre, as defined in the emerging Central Area Plan, r, within the city centre, the regeneratin areas f: 4 Except where the prpsed develpment departs significantly frm the terms f the site allcatin, particularly where the prpsal is fr mre vulnerable uses than thse fr which the site has been allcated (such a prpsal t build husing n a site that has been allcated fr ffices), in which case a Sequential Test shuld be submitted with the planning applicatin. 4

Bristl Develpment FramewrkPractice Nte (July FLOOD RISK SEQUENTIAL TEST Bristl Temple Quarter; Bristl Shpping Quarter; Newfundland Way; Nelsn Street and Lewins Mead; Redcliffe Way; Nrth Redcliffe; Central Harburside; and Cumberland Basin. These regeneratin areas reflect the areas identified by plicy BCS2 f the Cre Strategy as areas f fcus fr develpment and regeneratin, city centre gateways in need f imprvement r extensins t the city centre. Fig.3, verleaf, shws the lcatin f the city centre regeneratin areas. Suth Bristl, defined as all wards suth f the River Avn, r, within Suth Bristl, the regeneratin area f: Knwle West, as defined by the Knwle West Regeneratin Framewrk. Inner East Bristl, defined as thse parts f Ashley, Eastn and Lawrence Hill wards that are utside the city centre. The Nrthern Arc, defined as the wards f Lckleaze, Henbury, Suthmead, Kingswestn and Hrfield and the part f Avnmuth ward generally crrespnding t the residential and mixed-use areas east f the A4. Avnmuth Village, defined bradly as the residential and mixed-use part f Avnmuth ward west f the A4. An alternative area f search may be acceptable where it can be demnstrated with evidence that there is a specific need fr the prpsed develpment in that area that cannt be met elsewhere. Defining the search area: cnversins and replacement buildings Bristl, particularly Bristl City Centre, has a number f existing buildings that have reached the end f their useful life fr their present use and wuld benefit frm cnversin t ther uses, but are at risk f flding either at present r with climate change. It wuld be harmful t the cntinued regeneratin and sustainable develpment f Bristl fr these buildings t remain vacant and as such it will be a pririty fr the cuncil t supprt applicants in finding viable ways t bring them back int use. In situatins where an existing building has becme predminantly vacant because its existing use is n lnger viable and a cnversin t alternative uses is necessary t bring it back int use, the cuncil will cnsider the regeneratin benefits f its reuse and the implicatins f its remaining vacant. If the cuncil is satisfied that the benefits that wuld arise frm bringing the building back int use cannt be prvided by develpment n an alternative site, then the search area fr the Sequential Test can be the applicatin site alne and the Sequential Test thereby passed. In sme cases, it will nt be pssible t bring the building back int use withut sme increase in flrspace, such as thrugh the prvisin f additinal flrs r sme degree f extensin. In such cases the search area fr the Sequential Test may still be the site alne, but the prpsed additinal flrspace shuld nt be significantly mre than is required fr a deliverable scheme. The replacement f an existing building with a new, suitably fld-resilient design is likely t be preferable t the cnversin f an existing building if the expsure f peple and 5

FLOOD RISK SEQUENTIAL TEST prperty t flding is t be minimised. In such cases, subject t the cnsideratins set ut abve, the search area fr the Sequential Test can again be limited t the applicatin site. Applicants prpsing that the search area fr the Sequential Test shuld be limited t the site alne shuld set ut clearly their justificatin fr ding s as part f their planning applicatin. The justificatin shuld relate specifically t the site itself, such as imprving levels f activity and ftfall in an imprtant lcatin in a shpping area, the imprvement f an imprtant pedestrian rute that crsses r adjins the site r the impact n the lcal area f the existing building remaining vacant. 2.2.2. Identifying alternative sites The Sequential Test requires any alternative sites within the search area that are at lwer risk f flding and wuld be apprpriate fr the prpsed develpment t be identified. Alternative sites fr majr prpsals f 10 r mre dwellings r ver 1,000m² f nnresidential flrspace can be identified frm the cuncil s emerging Lcal Plan dcuments and the evidence prduced t supprt them, particularly the Strategic Husing Land Availability Assessment (SHLAA). Alternative sites fr small-scale prpsals f fewer than 10 dwellings r less than 1,000m² f nn-residential flrspace cannt readily be identified frm the abve surces. Applicants wishing t pursue a prpsal n such a site may instead gather evidence fr a Sequential Test by cnsulting lcal prperty agents listings. It is recmmended that a minimum f tw prperty agents be cnsulted. 2.2.3. Determining whether alternative sites are reasnably available A develpment prpsal will nly fail t pass the Sequential Test if alternative sites are identified within the search area that are at lwer risk f flding, wuld be apprpriate fr the prpsed develpment and are reasnably available fr develpment. A site is nly cnsidered t be reasnably available if it is bth deliverable and develpable as defined by the NPPF (Para.47, ftntes 11-12). Additinally, a site is nly cnsidered t be reasnably available if all f the fllwing apply: The site is within the agreed area f search. The site is f cmparable size and can accmmdate the requirements f the prpsed develpment. The site is either: Owned by the applicant; Fr sale at a fair market value; r Is publicly wned land that has been frmally declared t be surplus and is available fr purchase. The site is nt safeguarded in the Lcal Plan fr anther use. Sites are nt cnsidered t be reasnably available if they fail t meet any f the abve requirements r already have planning permissin fr a develpment that is likely t be implemented 5. 5 The Five Year Husing Land Supply reprt published annually by the cuncil prvides infrmatin n sites with planning permissin that the cuncil cnsiders likely t be implemented. 6

FLOOD RISK SEQUENTIAL TEST 3. Prpsals that pass the Sequential Test (r d nt require it) Prpsals that pass the Sequential Test (r d nt require it) will still need t respnd t and effectively mitigate the risk f flding n the site. This is dne thrugh a prcess f sitespecific Fld Risk Assessment and, in sme cases, the applicatin f the Exceptin Test. 3.1. The Exceptin Test Table 3 f the Technical Guidance t the NPPF (see Fig.2) sets ut the circumstances in which an Exceptin Test is als required. As set ut in the NPPF (para.102), fr the Exceptin Test t be passed: It must be demnstrated that the develpment prvides wider sustainability benefits t the cmmunity that utweigh fld risk, infrmed by the Strategic Fld Risk Assessment; and A site-specific Fld Risk Assessment must demnstrate that the develpment will be safe fr its lifetime taking accunt f the vulnerability f its users and the likely effects f climate change, withut increasing fld risk elsewhere, and, where pssible, will reduce fld risk verall. In applying the Exceptin Test t prpsals fr the cnversin r replacement f buildings, the cuncil will cnsider the extent t which the prvisin f any additinal flrspace is necessary t achieve a deliverable scheme that wuld prvide wider sustainability benefits. The Exceptin Test will nt be applied t prpsals that are als exempt frm the Sequential Test, such as changes f use and minr extensins and alteratins. The applicant fr prpsals that require an Exceptin Test shuld set ut clearly, as part f their applicatin, their case fr why the prpsal shuld pass it. 3.2. Site-specific Fld Risk Assessment Whether r nt an Exceptin Test is required, all prpsals fr develpment n sites at risk f flding shuld be accmpanied by a site-specific Fld Risk Assessment. As set ut in the Technical Guidance t the NPPF, this shuld identify and assess the risks f all frms f flding t and frm the develpment and demnstrate hw these fld risks will be managed s that the develpment remains safe thrughut its lifetime, taking climate change int accunt. Making reference t the SFRA and related studies, the Fld Risk Assessment shuld take accunt f the likely effects f climate change ver the lifetime f the develpment. Fr residential develpment this is generally held t be 100 years, while fr nn-residential develpment it is generally held t be 60 years. The cnsideratin f safety shuld cver nt just the use f the site r building(s) themselves, but als the prvisin f a safe rute fr access and escape suitable fr all users in the event f a fld. Prpsals that pass the Sequential Test shuld still fllw the Sequential Apprach t site design. Within the site, the mst vulnerable uses shuld be lcated n the parts f the site least affected by fld risk. The Fld Risk Assessment shuld demnstrate hw the Sequential Apprach has been fllwed in the layut f the develpment prpsal. 8

Bristl Develpment FramewrkPractice Nte (July FLOOD RISK SEQUENTIAL TEST Appendix 1: Surces f infrmatin Fld Risk Data Fld risk maps are published and updated regularly by the Envirnment Agency. The latest data fr Bristl, including prjectins fr fld risk with climate change, can be fund in the Strategic Fld Risk Assessment and related studies. This als includes infrmatin n surface water flding. Reasnably Available Sites Bristl prvides infrmatin abut husing sites as part f its evidence base, including ptential develpment sites and unimplemented planning permissins. Sites that have already been allcated fr develpment (r are prpsed t be) in Bristl are set ut in the Site Allcatins and Develpment Management dcument and Bristl Central Area Plan. Further sites may be identifiable thrugh lcal estate agents listings. Further Guidance Plicies fr planning and fld risk including the Sequential and Exceptin Tests are are enshrined in the Natinal Planning Plicy Framewrk (NPPF) and its accmpanying technical guidance. The NPPF is currently still supprted by the PPS25 Practice Guide. The plicies in the NPPF are als enshrined in plicy BCS16 f the adpted Bristl Cre Strategy (July 2011). The Envirnment Agency prvides Fld Risk Standing Advice t further assist planners and develpers. 9

FLOOD RISK SEQUENTIAL TEST Appendix 2: Fld Risk Vulnerability Classificatin Table 2 f the Technical Guidance t the Natinal Planning Plicy Framewrk: 10

Bristl Develpment FramewrkPractice Nte (July FLOOD RISK SEQUENTIAL TEST 11