IPS078 - Isle Of Wight Council

7 Wood Environment & Infrastructure Solutions UK LimitedIsle of Wight Level 2 SFRA – Flood Risk Information SheetGeneral informationSite AddressLand north of Perowne Way and west of Brook Close, Sandown.Site DescriptionSite IDCurrently in agricultural use, the topography is slightly undulating and slopes to the north towards the River Yar. Theboundaries are a mix of trees, hedgerows and scrub. Although the total area is greater, the developable area has beensubmitted as 2.0 hectares.IPS135Area (ha)3.2Current land useGreenfieldProposed allocation typeResidentialIndicative yield60Proposed developmentStandard detached/semis / affordableBaseline Flood Risk SummaryThere is a risk of tidal flooding to the site via the River Yar which runs adjacent to the northern boundary and is at an elevation of less than 2 m. The 21150.1% AEP tidal event covers around 30% of site. There has been historic flooding recorded across approximately 30% of the site, to the north (extendingbeyond the 2115 0.1% AEP tidal extent).There is potentially a risk of fluvial flooding. Approximately 5% of IPS135 on the northern side is located in FZ3, although it is unclear whether the risk is tidalor fluvial, or a combination of the two. The River Yar does have flood defences in the form of an embankment, but this only protects against the 20% AEPfluvial flood. As such, the site is not in an ABD.A small area in the northeast corner of the site is subject to high risk of SW flooding. Parts of the Perowne Way and other potential access roads such asMortonbook have a medium - low risk of SW flooding.There is a potential risk of GW flooding at the site despite the solid geology comprising mudstone overlain by slowly permeable seasonally waterlogged clay.The Level 1 SFRA found that high groundwater levels can impose a high baseflow on the River Yar and exacerbate fluvial flooding, so the proximity to thewatercourse at the low lying north of the site could pose a GW risk.There is no risk of reservoir flooding to the site.Sewer flooding was not identified as an issue in Sandown by the Level 1 SFRA.Site SuitabilityOn the basis of the information provided, this site is considered suitable for residential development subject to the consideration of policy and NPPFcompliance recommendations below.Policy Recommendations In accordance with PPG Tables 2 & 3, housing is classed as more vulnerable and thus FZ3 should be avoided or the Exception Test would need to bepassed.The Exception test would need to robustly demonstrate that the wider sustainability benefits outweigh flood risk and that the development will besafe throughout its lifetime, to include allowances for climate change.In accordance with NPPF Footnote 50, a site-specific FRA is required due to part of the site being located within FZ3 and in excess of 1 ha in area.Drainage water discharge points to the River Yar will be subject to a FRAP from the EA.Site-Specific Recommendations for NPPF Compliant Development Safe access and egress to the site should be from Perowne Way.Further investigation is required into tidal and fluvial flood risks, including the context of historic outlines and 2115 scenarios.Development of housing should be directed away from the north of the site, following a sequential approach of selecting the area of lowest risk.Sustainable drainage solutions should be implemented, where possible (see drainage management recommendations below).Further investigation is needed into GW flood risk.The construction and operation of the development should not exacerbate flood risk to the site or 3rd parties. All feasible SuDS options should be assessed, whilst adhering to the SuDS hierarchy, as set out in the SRFA report.It is unlikely that infiltration techniques will be feasible, due to impermeable soils and geology and proximity to the Yar.The greenfield runoff rate should be determined for the site using current best practice. This will allow for the appropriate sizing of attenuation andconveyance SuDS to ensure that sufficient space for drainage infrastructure is provided in developing site masterplans.Drainage design should include recommended allowances for climate change.As SW discharge would likely be to the River Yar, appropriate consultations should be had regarding FRAP application requirements.SuDS should not be constructed in flood risk areas (as confirmed by the hydraulic model and not the existing mapping)Drainage Management Recommendations October 2018

8 Wood Environment & Infrastructure Solutions UK LimitedIsle of Wight Level 2 SFRA – Flood Risk Information SheetGeneral informationSite AddressLand adjacent to Perowne Way, Sandown.Site DescriptionThe site is irregular in shape and currently in agricultural use with relatively flat topography in some areas and in othersslightly undulating and sloping towards the River Yar in the north. The boundaries are a mix of trees, hedgerows and scrub.The site is located to the west of and immediately adjacent to IPS135.Site IDIPS217Area (ha)6.8Current land useGreenfieldProposed allocation typeResidentialIndicative yield65Proposed developmentStandard detached/semis / affordableBaseline Flood Risk SummaryThere is a risk of tidal flooding to the site. The River Yar runs adjacent to the northern edge of the site, which is at a low elevation of under 2 m. The 21150.5% AEP tidal event covers around 25% of site. There has been historic flooding recorded across approximately 70% of the site, to the north (extendingbeyond the 2115 0.1% AEP tidal extent).There is potentially a risk of fluvial flooding to the site, confined to the north-western edge. Here the site is directly adjacent to the River Yar. Approximately2% of the site on the north-western corner is located in FZ2, although it is unclear whether the risk is tidal or fluvial, or a combination of the two. The RiverYar does have flood defences, in the form of an embankment, but this only protects against the 20% AEP fluvial flood. As such, the site is not in an ABD.There is a SW flood risk to the site. SW originates off-site on Perowne Way, flowing through the site to the Yar via Sandham Close. The risk is classified as highon site, and medium – low on the access roads of Sandham Close and Perowne Way.There is a potential risk of GW flooding at the site despite the solid geology comprising mudstone overlain by slowly permeable seasonally waterlogged clay.The Level 1 SFRA found that high groundwater levels can impose a high baseflow on the River Yar and exacerbate fluvial flooding, so the proximity to thewatercourse at the low lying north of the site could pose a GW risk.There is no risk of reservoir flooding to the site.Sewer flooding was not identified as an issue in Sandown by the Level 1 SFRA.Site SuitabilityOn the basis of the information provided, this site is considered suitable for residential development subject to the consideration of policy and NPPFcompliance recommendations below.Policy Recommendations In accordance with PPG Tables 2 & 3, housing is classed as more vulnerable and thus FZ3 should be avoided or the Exception Test would need to bepassed.The Exception test would need to robustly demonstrate that the wider sustainability benefits outweigh flood risk and that the development will besafe throughout its lifetime, to include allowances for climate change.In accordance with NPPF Footnote 50, a site-specific FRA is required due to part of the site being located within FZ2 and in excess of 1 ha in area.Drainage water discharge points to the River Yar will be subject to a FRAP from the EA.Site-Specific Recommendations for NPPF Compliant Development Safe access and egress to the site should be from Perowne Way, via the unnamed road providing potential access to the middle of the site ratherthan Sandham Close.Further investigation is required into tidal and fluvial flood risks, including the context of historic outlines and 2115 scenarios.Development of housing should be directed away from the north of the site, following a sequential approach of selecting the area of lowest risk.Sustainable drainage solutions should be implemented, where possible (see drainage management recommendations below).Further investigation is needed into GW flood risk.The construction and operation of the development should not exacerbate tidal, fluvial or SW flood risk to the site or 3rd parties.Drainage Management Recommendations As the site is currently greenfield land, housing development will create more impermeable areas.All feasible SuDS options should be assessed, whilst adhering to the SuDS hierarchy, as set out in the SRFA report.It is unlikely that infiltration techniques will be feasible, due to impermeable soils and geology.SW should be directed away from the housing and drained by gravity toward the River Yar or its floodplain, without increasing flood risk to 3rdparties downstream. This should be detailed in a drainage strategy.The greenfield runoff rate should be determined for the site using current best practice. This will allow for the appropriate sizing of attenuation andconveyance SuDS to ensure that sufficient space for drainage infrastructure is provided in developing site masterplans.Drainage design should include recommended allowances for climate change.As SW discharge would likely be to the River Yar, appropriate consultations should be had regarding FRAP application requirements.October 2018

ite BoundaryIPS13504080120160Scale at A3: 1:4,000200m85000 Crown Copyright. All rights reserved. Licence number AL100001776.IPS077Isle of WightStrategic Flood Risk ODEL\PROJECTS\ HM-250\41017 LDN IoW SFRA\GIS\MXD\41017Ldn017.mxd Originator: ivano.pola85200IPS217Site location planIPS135 / IPS217Land north of Perowne Way and west ofBrook Close, Sandown / Land adjacentPerowne Way, SandownOctober 2018

459000459200459400459600459800460000KeySite Bound aryMain RiversFlood De fe nc e s85600Are as Be ne fiting from Flood De fe nc e sHis toric alFlood ingFlood Z one 2Flood Z one 3Tid alFlood Z one 2with c lim ate c hangeto 211585400Tid alFlood Z one 3with c lim ate c hangeto 2115IPS135IPS217Flood Z one 2-land ass e s s e d as having be twe e n a1in 100and 1in 1,000annual probabilityofrive rflood ing (1% –0.1%),orbe twe e n a 1 in 200 and 1 in 1,000 annualprobabilityofs e aflood ing (0.5% – 0.1%)in anyye ar.Flood Z one 3 -land ass e s s e d as having a 1 in 100 orgreate rannualprobabilityofrive rflood ing ( 1%),ora1in200orgre ate rannual probabilityofflood ing from the s e a( 0.5%)in anyye ar.85200Future flood zone s 2and 3d is playtid alflood e xte \\s alfs 10.global.am e c .c om \s hare d \ MODEL\PROJECTS\HM250\41017LDN IoW SFRA\GIS\MXDScale atA3:1:4,000 Crown Copyright.Allrights re se rve d.Lic e nc e num be rAL100001776.Is le ofWightStrate gic Flood Ris k As s e s s m e ntPresent day fluvial and tidal Flood Zoneextents, and future tidal flood zone extentswith climate change to 2115IPS135 / IPS217Land north of Perowne Way and west ofBrook Close, Sandown / Land adjacentPerowne Way, SandownOc tobe r2018

459000459200459400459600459800460000KeySite Bou nda ryHig hriskMe diu m risk8540085600LowriskIPS13585200IPS217Hig h risk –la nd a sse sse d a s ha ving a 1in 30or g re a te ra nnu a l prob a b ilityof su rfa ce wa te r flooding (3.33%)in a nyye a r.Me diu m risk –la nda sse sse da s ha ving b e twe e n a 1in 30a nd1in 100a nnu a l prob a b ilityof su rfa ce wa te r flooding(3.33% -1%)in a nyye a r.Low risk –la nda sse sse da s ha ving a b e twe e n a 1in 100a nd1in 1,000a nnu a lprob a b ilityof su rfa ce wa te r flooding(0.1% -1%)in a nyye a r.04080120160Sca le a t A3:1:4,000200m85000IPS07784800G:\MO DEL\PRO JECTS\HM250\41017LDN IoW SFRA\GIS\MXD\41017Ldn019.mxd O rig ina tor:sa ra h.b u tle r Crown Copyrig ht.Allrig hts re se rve d.Lice nce nu m b e r AL100001776.Isle of W ig htStra te g icFloodRisk Asse ssm e ntSurface water flood risk extentIPS135 / IPS217Land north of Perowne Way and west ofBrook Close, Sandown / Land adjacentPerowne Way, SandownO ctob e r 2018

459000459200459400459600459800Key460000Site BoundaryContour line (interval 2m)20Elevation - 1m LiDAR DTM85600261010854000mIPS135IPS2170Light Detection and Ranging (LiDAR) is an airbornemapping technique, which uses a laser to measurethe distance between the aircraft and the ground.The spatial resolution is 1m. This can be used toprovide information about the elevation andgradient of the site.852004080120160Scale at A3: 1:4,000200m Crown Copyright. All rights reserved. Licence number AL100001776.20101085000010Isle of WightStrategic Flood Risk shared\MODEL\PROJECTS\ HM-250\41017 LDN IoW SFRA\GIS\MXD\41017Ldn020 IPS135 217.mxd Originator: ivano.pola10020LiDAR ground elevationIPS135 / IPS217Land north of Perowne Way and west ofBrook Close, Sandown / Land adjacentPerowne Way, SandownOctober 2018

H1 Wood Environment & Infrastructure Solutions UK LimitedDraft - see disclaimerAppendix HIPS138B - Land on the south-west side of BuckburyLane, NewportOctober 2018Doc Ref. 41017-C005-Draft IoW Level 2 SFRA

9 Wood Environment & Infrastructure Solutions UK LimitedIsle of Wight Level 2 SFRA – Flood Risk Information SheetGeneral informationSite AddressLand on the south-west side of Buckbury Lane opposite Powell Close and Buckbury Close, Newport.Site DescriptionThe site comprises pasture with some areas of scrub. It is bounded by hedges and trees within some larger trees tothe south of the site. The site falls to the south from the north and Buckbury Lane.Site IDIPS138bArea (ha)1.6Current land useGreenfieldProposed allocation typeResidentialIndicative yield1-2Proposed developmentAspirational/standard detached/semiBaseline Flood Risk SummaryThere is no tidal flood risk to the site.The site is at risk of fluvial flooding. The northern edge of the site is directly adjacent to a stream which forms a tributary of the River Medina. The origin andcatchment of the stream is unclear, and may be culverted under Buckbury Lane. Existing FZ mapping places approximately 25% of the site on the north andwest side in FZ3 as a result of this stream. To the south of the site, a second stream runs east to west, but does not impact the site.There is a very low SW flood risk to the site. A SW flowpath follows the shape of the stream tracing the northern edge of the site. The SW appears to becontained within the channel, and may not impact the site.There is a low risk of GW flooding due to relatively impermeable soils and geology. Solid geology at the site comprises clay silt and sand, overlain by soilswhich are slowly permeable, seasonally waterlogged and consist of clay.There is no risk of reservoir flooding to the site.Sewer flooding was not identified as an issue in Newport by the Level 1 SFRA.Site SuitabilityOn the basis of the information provided, this site is considered suitable for residential development subject to the consideration of policy and NPPFcompliance recommendations below.Policy Recommendations In accordance with PPG Tables 2 & 3, housing is classed as more vulnerable and thus FZ3 should be avoided or the Exception Test would need to bepassed.The Exception test would need to robustly demonstrate that the wider sustainability benefits outweigh flood risk and that the development will besafe throughout its lifetime, to include allowances for climate change.In accordance with NPPF Footnote 50, a site-specific FRA is required, as part of the site is located within FZ3.Drainage water discharge points to the adjacent watercourse will be subject to an OWC from the LLFA.Site-Specific Recommendations for NPPF Compliant Development Safe access and egress to the site should be from Buckbury Lane.Hydraulic modelling should be undertaken to more accurately determine flood extents on the site as it is likely that the EA mapping overestimatesthe extents which are not commensurate with the watercourse catchment size and topography which falls steeply to the southwest.Development of housing should be directed away from the north-west of the site, following a sequential approach of selecting the area of lowest risk.The construction and operation of the development should not exacerbate the fluvial or SW flood risk to the site or 3rd parties.Drainage Management Recommendations All feasible SuDS options should be assessed, whilst adhering to the SuDS hierarchy, as set out in the SRFA report.Infiltration techniques may be feasible. If so this would be the preferred method and the feasibility should be investigated via site investigation.The Greenfield runoff rate should be determined for the site using current best practice. This will allow for the appropriate sizing of attenuation andconveyance SuDS (if required).Drainage design should include recommended allowances for climate change.If a SW discharge to the adjacent watercourse in needed, appropriate consultations should be had regarding OWC application requirements.October 2018

ite Boundary04080120160Scale at A3: 1:4,000200m88800 Crown Copyright. All rights reserved. Licence number AL100001776.Isle of WightStrategic Flood Risk ODEL\PROJECTS\ HM-250\41017 LDN IoW SFRA\GIS\MXD\41017Ldn017.mxd Originator: ivano.pola89000IPS138bSite location planIPS138bLand on the south-west side of BuckburyLane opposite Powell Close and BuckburyClose, Newport.October 2018

451000451200451400451600451800452000KeySite Bound aryMain RiversFlood De fe nc e sAre as Be ne fiting from Flood De fe nc e s89400His toric alFlood ingFlood Z one 2Flood Z one 3Tid alFlood Z one 2with c lim ate c hangeto 211589200Tid alFlood Z one 3with c lim ate c hangeto 211589000IPS138bFlood Z one 2-land ass e s s e d as having be twe e n a1in

0 40 80 120 160 200 m Hgi rshi alk– nad sse sse ad sha nivgani o13 0 gr re a te r annu ap lrob a botil isyfu rfaecw a tefolr odni3ni3%ag 3. )(n y ey a r. Me dui mrsail k– n ad sse ssead hsa nivgb e twe e nani3 10 annia110 d0 nnu ap lrob a boti