UNIT 1A, BOTLEY ROAD, OXFORD, OX2 0HD
FLOOD RISK ASSESSMENT Final Report v1.1
March 2021
Weetwood Services Ltd Suite C22 Joseph’s Well Hanover Walk Leeds LS3 1AB
0113 244 1377 [email protected] www.weetwood.net
Unit 1A, Botley Road, Oxford, OX2 0HD Flood Risk Assessment
Report Title Unit 1A, Botley Road, Oxford, OX2 0HD
Flood Risk Assessment Final Report v1.1
Client Westminster Project Services Limited
Date of issue 23 March 2021
Prepared by Kevin Tilford BSc MSc PhD MBA CWEM FCIWEM CEnv Managing Director
Checked by: Keely Bonser BSc (Hons) MSc PhD Associate Director
Approved by Kevin Tilford BSc MSc PhD MBA CWEM FCIWEM CEnv Managing Director
This document has been prepared solely as a Flood Risk Assessment for Westminster Project Services Limited. This report is confidential to Westminster Project Services Limited and Weetwood Services Ltd accepts no responsibility or liability for any use that is made of this document other than by Westminster Project Services Limited for the purposes for which it was originally commissioned and prepared.
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Unit 1A, Botley Road, Oxford, OX2 0HD Flood Risk Assessment
Contents
Signature Sheet i Contents ii List of Tables, Figures & Appendices iii
1 INTRODUCTION...... 1 1.1 Purpose of Report ...... 1 1.2 Structure of the Report ...... 1 1.3 Relevant Documents ...... 1
2 SITE DETAILS AND PROPOSED DEVELOPMENT...... 2 2.1 Site Location ...... 2 2.2 Existing and Proposed Development ...... 2 2.3 Waterbodies in the Vicinity of the Site ...... 2 2.4 Topography ...... 3 2.5 Flood Zone Designation ...... 3
3 PLANNING POLICY AND GUIDANCE ...... 6 3.1 National Planning Policy and Guidance ...... 6 3.2 Local Planning Policy and Guidance ...... 6
4 REVIEW OF FLOOD RISK ...... 8 4.1 Sequential Test and Exception Test ...... 8 4.2 Historical records of flooding ...... 8 4.3 Flood defences ...... 9 4.4 Flood Risk from the River Ribble ...... 9 4.5 Flood Risk from Surface Water ...... 12 4.6 Flood Risk from Reservoirs, Canals and Other Artificial Sources ...... 12 4.7 Flood Risk from Groundwater ...... 12
5 FLOOD RISK MITIGATION MEASURES ...... 14
6 SURFACE WATER MANAGEMENT ...... 15
7 SUMMARY AND RECOMMENDATIONS ...... 16
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Unit 1A, Botley Road, Oxford, OX2 0HD Flood Risk Assessment
List of Tables
Table 1: Peak Modelled Water Levels ...... 10
List of Figures
Figure 1: Site Location and Watercourses ...... 2 Figure 2: Digital Terrain Model - LiDAR ...... 3 Figure 3: Flood Map for Planning ...... 4 Figure 4: Flood Map (Main Rivers) ...... 4 Figure 5: Functional Floodplain ...... 5 Figure 6: Extent of Historic Flooding ...... 8 Figure 7: Recorded Flood Events ...... 9 Figure 8: Model Node Locations ...... 10 Figure 9: Peak Flood Depth in the Vicinity of the Site...... 11 Figure 10: Flood Hazard (1 in 100 AEP plus 35% climate change event) ...... 11 Figure 11: Flood Risk from Surface Water ...... 12 Figure 12: Risk of Reservoir Flooding ...... 13 Figure 13: JBA Groundwater Flood Map ...... 13 Figure 14: Environment Agency Flood Warning Areas ...... 14
List of Appendices
Appendix A: Existing and Proposed Site Layout
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Unit 1A, Botley Road, Oxford, OX2 0HD Flood Risk Assessment
1 INTRODUCTION
1.1 PURPOSE OF REPORT Weetwood Services Ltd ('Weetwood') has been instructed by Westminster Project Services Ltd to prepare a Flood Risk Assessment (FRA) report to accompany a planning application for proposed changes to Unit 1a Botley Road, Oxford (“the site”). The assessment has been undertaken in accordance with the requirements of the revised National Planning Policy Framework (NPPF) updated on 19 June 2019 and the National Planning Practice Guidance (NPPG) updated on 1 October 2019.
1.2 STRUCTURE OF THE REPORT The report is structured as follows:
Section 1 Introduction and report structure Section 2 Presents national and local flood risk and drainage planning policy Section 3 Provides background information relating to the development site, the development proposals, ground conditions and existing site access arrangements Section 4 Assesses the potential sources of flooding to the development site Section 5 Presents flood risk mitigation measures based on the findings of the assessment Section 6 Addresses the effect of the proposed development on surface water runoff Section 7 Presents a summary of key findings and recommendations
1.3 RELEVANT DOCUMENTS The assessment has been informed by the following documents: • Oxford City Level 1 Strategic Flood Risk Assessment, November 2017 • West Oxford / New Botley Area Flood Response Plan, Oxford Area Flood Partnership, August 2014 • Oxford City Council pre-application opinion letter dated 8 January 2021 (letter ref: 20/03265/PAC) • Oxford City Council Sustainable Drainage - Design and Evaluation Guide, 2018 • Oxford Baseline Hydraulic Modelling Report, CH2M, Doc ref: RP-HY-0147, March 2018
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Unit 1A, Botley Road, Oxford, OX2 0HD Flood Risk Assessment
2 SITE DETAILS AND PROPOSED DEVELOPMENT
2.1 SITE LOCATION The application site is located within the Botley Road retail parks area on the western city approach, to the south of Botley Road, near to the junction with Seacourt Park and Ride and next to Earl Street, a residential road. The centre of the site is at Ordnance Survey National Grid Reference SP 4954 0616 as shown in Figure 1.
Figure 1: Site Location and Watercourses
2.2 EXISTING AND PROPOSED DEVELOPMENT Unit 1a is a single storey unit with a floor area of 620 sq m. The unit is part of a larger building providing two additional units (Unit 1 and Unit 2). The site is served by approximately 137 customer car parking spaces. The proposals (refer Appendix A ) are for the construction of a mezzanine of 553 sq m and modernisation of the shopfront, including a new freestanding signage feature on the shop front and minor works to the front of the store to provide pedestrian access to the shop front. The NPPG classifies retail and food retailer use as Less Vulnerable to flood risk. As such there is no increase to the vulnerability of the use of the site.
2.3 WATERBODIES IN THE VICINITY OF THE SITE There is a relatively complex network of ordinary watercourses and main rivers in the vicinity of the site (refer Figure 1 ): • Bulstake Stream, a main river, flows in a southerly direction approximately 150 m east of the site. • Botley Stream flows in a south-easterly direction and flows into Bulstake Stream approximately 240 m north-east of the site. • An unnamed drain (ordinary watercourse) flows in a south-easterly direction. The watercourse passes within approximately 200 m west/south-west of the site.
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Unit 1A, Botley Road, Oxford, OX2 0HD Flood Risk Assessment
• Osney Ditch/Osney Stream, a main river, flows in a southerly direction, approximately 575 m east of the site • Wytham Stream/Seacourt Stream flows in a south-easterly direction approximately 500 m west/south- west of the site. • The River Thames (not shown on Figure 1 ) flows in a southerly direction to the north and east of the site. At its closest, the Thames is approximately 930 m east of the site.
2.4 TOPOGRAPHY LiDAR data has been used to develop a digital terrain model of the site and surrounding area (Figure 2 ). Ground levels in the car park and adjacent to the unit are indicated to be 57.3 m AOD, increasing to approximately 57.5 m AOD immediately in front of the unit. Levels along Botley Road adjacent to the site are indicated to be 57.2 m AOD.
Figure 2: Digital Terrain Model - LiDAR
2.5 FLOOD ZONE DESIGNATION
The Environment Agency Flood Map for Planning (Rivers and Sea) 1 (Figure 3) indicates that the site is located in flood zone 3. However, Appendix 2 of the 2017 Level 1 SFRA (see extract in Figure 4 ) indicates Unit 1a to be located in flood zone 1, with the surrounding land, including the car park to the north of the unit indicated to be located in flood zone 2 or flood zone 3.
The NPPG defines flood zones as follows 2: • Flood Zone 1: Low Probability. Land having a less than 1 in 1,000 annual probability of river or sea flooding • Flood Zone 2: Medium Probability. Land having between a 1 in 100 and 1 in 1,000 annual probability of river flooding or between a 1 in 200 and 1 in 1,000 annual probability of sea flooding • Flood Zone 3a: High Probability. Land having a 1 in 100 or greater annual probability of river flooding or a 1 in 200 or greater annual probability of sea flooding • Flood Zone 3b: Functional Floodplain. Land where water has to flow or be stored in times of flood.
1 https://flood-map-for-planning.service.gov.uk/ 2 https://www.gov.uk/guidance/flood-risk-and-coastal-change#flood-zone-and-flood-risk-tables
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Unit 1A, Botley Road, Oxford, OX2 0HD Flood Risk Assessment
Figure 3: Flood Map for Planning Source: gov.uk website; Accessed: 22 June 2020
Figure 4: Flood Map (Main Rivers) Source: 2017 Level 1 SFRA – Appendix 2; Ref WHS 1459-T01-001 C)
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Unit 1A, Botley Road, Oxford, OX2 0HD Flood Risk Assessment
Key features of the Flood Map for Planning are: • Where an area benefits from formal flood defences providing a minimum standard of protection, the defended area may be indicated as an area benefiting from flood defences. However, not all areas are indicated as such, and unless specifically indicated, the Flood Map for Planning conservatively shows land at risk of flooding in the absence of flood defences. • The flood zones do not take account of the possible impacts of climate change and consequent changes in the future probability of flooding. Flood zone 3b (functional floodplain) is not separately distinguished on the Flood Map for Planning. However, according to Appendix 10 of the 2017 Level 1 SFRA (see extract in Figure 5 ) Unit 1a is shown not to be in flood zone 3b although part of the car park to the north of the unit and adjacent land to the south and east is indicated to be in “flood zone 3b developed”.
Figure 5: Functional Floodplain Source: 2017 Level 1 SFRA – Appendix 10; Ref WHS 1459-T01-009)
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Unit 1A, Botley Road, Oxford, OX2 0HD Flood Risk Assessment
3 PLANNING POLICY AND GUIDANCE
3.1 NATIONAL PLANNING POLICY AND GUIDANCE The NPPF sets out government's planning policies for England and how these are expected to be applied. The NPPF seeks to ensure that flood risk is considered at all stages in the planning process and is appropriately addressed. Footnote 50 of the NPPF states that a site-specific flood risk assessment should be submitted for all development proposed in Flood Zone 2 and Flood Zone 3 whilst in Flood Zone 1, an assessment should accompany all proposals involving: sites of 1 hectare or more; land identified as having critical drainage problems or as being at increased flood risk in future; or land that may be subject to other sources of flooding, where its development would introduce a more vulnerable use. NPPF paragraph 155 states that inappropriate development in areas at risk of flooding should be avoided by directing development away from areas at highest risk but accepts that where development is necessary in such areas, the development should be made safe for its lifetime without increasing flood risk elsewhere. The policy of seeking to direct development away from areas at highest risk of flooding is implemented through the application of the sequential test (NPPF paragraph 158). Paragraph 159 of the NPPF states that if it is not possible for a development to be located in zones with a lower risk of flooding, taking into account wider sustainable development objectives, the exception test may have to be applied. The need for the exception test will depend on the flood zone of the site and of the vulnerability of the development proposed (as set out in NPPG Table 2 and 3). NPPF paragraph 160 states that application of the exception test for development proposals at the application stage should be informed by a site-specific flood risk assessment. For the test to be passed it should be demonstrated that: the development would provide wider sustainability benefits to the community that outweigh the flood risk; and the development will be safe for its lifetime taking account of the vulnerability of its users, without increasing flood risk elsewhere, and, where possible, will reduce flood risk overall. NPPF Paragraph 161 states that both elements of the exception test should be satisfied for development to be permitted. NPPF Paragraph 163 states that development should only be allowed in areas at risk of flooding if it incorporates sustainable drainage systems unless there is clear evidence that this would be inappropriate whilst NPPF Paragraph 165 states that applications for major developments should incorporate sustainable drainage systems to appropriate operational standards and with maintenance arrangements in place unless there is clear evidence that this would be inappropriate. Non-statutory technical standards for sustainable drainage were published by DEFRA in March 2015. The standards set out how surface water runoff generated during the present day 1 in 30 and 1 in 100 AEP rainfall events and for events exceeding the present day 1 in 100 AEP event should be managed, how peak runoff rates should be restricted and how runoff volumes should be controlled.
3.2 LOCAL PLANNING POLICY AND GUIDANCE The Oxford Local Plan 2036 was adopted in June 2020. The following policies relate to flood risk and drainage: • Policy RE1 Sustainable Design and Construction states that planning permission will only be granted where it can be demonstrated that flood risk is minimised (including flood resilient construction).
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Unit 1A, Botley Road, Oxford, OX2 0HD Flood Risk Assessment
• Policy RE3 Flood Risk Management, states that planning permission may be granted for development in Flood zone 3b for water-compatible uses or essential infrastructure; or where it is on previously developed land and delivers an improvement to the existing situation in terms of flood risk. Planning applications for development within Flood Zone 2, 3, on sites larger than 1 ha in Flood Zone 1 and, in areas identified as Critical Drainage Areas, must be accompanied by a Site Specific Flood Risk Assessment. The FRA must be undertaken in accordance with up to date flood data, national and local guidance on flooding and consider flooding from all sources. The suitability of developments proposed will be assessed according to the sequential approach and exceptions test as set out in Planning Practice Guidance. • Policy RE4: Sustainable and Foul Drainage, Surface and Groundwater Flow states that all development proposals will be required to manage surface water through Sustainable Drainage Systems (SuDS) or techniques to limit run-off and reduce the existing rate of run-off on previously developed sites. Surface water runoff should be managed as close to its source as possible, in line with the drainage hierarchy. The policy also states that proposals should have no adverse impact on groundwater flow and that all new development on brownfield sites should provide separate sewer systems.
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Unit 1A, Botley Road, Oxford, OX2 0HD Flood Risk Assessment
4 REVIEW OF FLOOD RISK
4.1 SEQUENTIAL TEST AND EXCEPTION TEST The proposals relate to an existing retail unit. As such application of the flood risk sequential test is not appropriate. According to Table 1 of the NPPG, the exception test need not be applied for Less Vulnerable development in flood zone 2 or flood zone 3a. Irrespective, the assessment presented in this report demonstrates that the proposed development will be safe for its lifetime and will not increase flood risk elsewhere, and in so doing addresses the second part of the exception test.
4.2 HISTORICAL RECORDS OF FLOODING According to the 2017 Level 1 SFRA, nine flood events have been recorded in the Oxford area from 1947 onwards, with the most recent being in 2007, 2012 and 2014. The maximum flood extent of all recorded historic flooding is shown in Appendix 7 of the 2017 Level 1 SFRA (refer extract in Figure 6 ).
Figure 6: Extent of Historic Flooding Source: 2017 Level 1 SFRA – Appendix 7; Ref WHS 1459-T01-006
A more detailed record of the extent of historic flood events is provided in the Environment Agency recorded flood outlines dataset (refer Figure 7 ). According to these records, the most severe flood event in the vicinity of the site was the July 2007 event. According to the Environment Agency records, the car park, and land to the east, west and south of the unit was flooded, although it is believed that no flooding of the unit itself occurred.
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Unit 1A, Botley Road, Oxford, OX2 0HD Flood Risk Assessment
Figure 7: Recorded Flood Events Source: open.gov website: Accessed March 2021
4.3 FLOOD DEFENCES According to the 2017 Level 1 SFRA, the Environment Agency does not own or maintain any formal flood defences in Oxford but are responsible for deploying demountable flood defences at Osney Island (approximately 700 m east of the site) and New Hinksey (2.7 km south-east of the site) during significant flood events. Oxford Council does not own or maintain formal flood defences but are responsible for operating demountable flood defences at Bulstake Close in New Botley (approximately 125 m north of Unit 1a) and a number of pumps. There are, however, a number of potentially discontinuous, informal defences (retaining walls) in Osney and New Botley along Osney Stream and Osney Ditch. According to the 2017 Level 1 SFRA, the standard of protection for these informal defences is unknown but unlikely to be greater than 1 in 25.
4.4 FLOOD RISK FROM THE RIVER THAMES AND ASSOCIATED WATERCOURSES Between 2015 and 2018, the existing 1D/2D (Flood Modeller / TUFLOW) hydraulic model of the River Thames developed in 2014 as part of the Oxford Flood Risk Mapping Study was updated by CH2M on behalf of the Environment Agency. Full details of the update of the hydraulic model and associated hydrology are provided in the hydraulic modelling report (refer Section 1.3 of this report for the report reference). Full model outputs from the 2018 River Thames model were provided to Weetwood on 16 February 2021 for use under licence (EA ref: THM205465). Given that the 2018 modelling supercedes the modelling presented in the 2017 Level 1 SFRA, outputs from the 2018 model are taken to represent the best available information. Peak water levels from the 1D component of the 2018 model for a number of watercourses in the vicinity of the site (refer Figure 8) are presented in Table 1 below. It is apparent from the model outputs that the difference in peak levels for different events is relatively small, with the peak level for the present day 1 in 1,000 annual exceedance probability (AEP) event approximately 200 mm greater than the peak level for the present day 1 in 100 AEP event. The outputs also indicate that the peak levels for the present day 1 in 1,000 event are broadly comparable to the 1 in 100 AEP plus 35% climate change event.
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Unit 1A, Botley Road, Oxford, OX2 0HD Flood Risk Assessment
Figure 8: Model Node Locations Source: 2018 Oxford Baseline Hydraulic Modelling Report (Figure 38)
Table 1: Peak Modelled Water Levels Oxford Baseline Hydraulic Modelling Report (Table 36)
Peak modelled level (m AOD) Present day events Climate change events Model Node / Watercourse 1 in 100 1 in 100 1 in 100 1 in 1,000 1 in 100 +35% +25% +70% 2 – Seacourt at Botley Road 57.44 57.67 57.58 57.65 57.82 3 – Bulstake at Botley Road 57.31 57.52 57.44 57.50 57.69 4 - Osney Ditch 57.52 57.73 57.65 57.71 57.87 5 – Thames at Botley Road 57.21 57.46 57.37 57.44 57.62 7 – Seacourt at Willow Walk 56.83 57.02 56.94 57.01 57.18 8 - Bulstake at Willow Walk 56.85 57.06 56.97 57.04 57.21
To determine potential flood depths at the site for a range of events, outputs from the 2D domain have been extracted from the model and are presented in Figure 9 below.
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Unit 1A, Botley Road, Oxford, OX2 0HD Flood Risk Assessment
Figure 9: Peak Flood Depth in the Vicinity of the Site Source: Outputs from 2018 Hydraulic Model (2D)
According to the 2D model outputs, the land adjacent to Unit 1a is indicated to flood to a depth of up to 0.2 m during the present day 1 in 100 AEP event, and up to 0.4 m during the present day 1 in 1,000 AEP event and 1 in 100 AEP plus 35% climate change event. For all events, flood depths are indicated to be approximately 0.15 m deeper in the northern part of the car park and up to 0.25 m deeper on Botley Road adjacent to the retail park. The flood hazard in the vicinity of the site (refer Figure 10 ) varies from Moderate adjacent to Unit 1a to Significant in the northern part of the car park and along Botley Road adjacent to the site.
Figure 10: Flood Hazard (1 in 100 AEP plus 35% climate change event) Source: Outputs from 2018 Hydraulic Model (2D)
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Unit 1A, Botley Road, Oxford, OX2 0HD Flood Risk Assessment
According to the 2014 West Oxford / New Botley Area flood response plan prepared by the Oxford Area Flood Partnership (partner members include Oxford City Council, Oxford County Council, Environment Agency and Thames Water), flooding to the west of Oxford “generally develops slowly, giving time to respond ”. Outputs from the 2018 hydraulic model confirm this, with peak levels for the 1 in 100 AEP event (and greater) occurring approximately 5 days from the time that levels begin to rise.
4.5 FLOOD RISK FROM SURFACE WATER According to Appendix 4 of the Level 1 SFRA, the site is not at risk of surface water flooding (refer extract in Figure 11).
4.6 FLOOD RISK FROM RESERVOIRS, CANALS AND OTHER ARTIFICIAL SOURCES According to Environment Agency mapping (refer Figure 12) the land in the vicinity of the site is at risk of reservoir flooding although Unit 1a itself is indicated not to be at risk. According to the 2017 Level 1 SFRA, this risk is associated with the failure of the Farmoor Reservoir (4.5 km west of the site). However, as stated in the 2017 Level 1 SFRA, reservoir failure has a very low probability of occurrence and reservoir regulation seeks to ensure that all reservoirs are properly maintained and monitored in order to detect and repair any problems. On this basis, the risk of reservoir flooding is assessed to be very low. There are no canals in the vicinity of the site.
4.7 FLOOD RISK FROM GROUNDWATER The JBA Groundwater Flood Risk Indicator map ( Figure 13) indicates that the site is not at risk of groundwater flooding. Irrespective, the site comprises entirely of impermeable surfaces that would prevent the emergence of groundwater.
Figure 11: Flood Risk from Surface Water Source: 2017 Level 1 SFRA – Appendix 4; Ref WHS 1459-T01-003 C
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Unit 1A, Botley Road, Oxford, OX2 0HD Flood Risk Assessment
Figure 12: Risk of Reservoir Flooding Source: gov.uk website; Accessed: 21 March 2021
Figure 13: JBA Groundwater Flood Map Source: Blue Sky Maps; Accessed ©Weetwood 5135/FRA/Final/v1.012021-03-23 www.weetwood.net 13 Unit 1A, Botley Road, Oxford, OX2 0HD Flood Risk Assessment 5 FLOOD RISK MITIGATION MEASURES Based on the assessment of flood risk presented in this report and taking into consideration the nature of the proposed development it is recommended that the proposed development could proceed in accordance with planning policy, and specifically subject to: • The implementation of a Flood Warning and Evacuation Plan. The objective of the plan would be to reduce the risk to property and life by ensuring that all employees and visitors are aware of the potential risk of flooding and the procedures that should be followed if flooding is forecast, during flooding and following an ‘all-clear’ notification. The site is included in an Environment Agency flood warning area (see Figure 14). This provides the opportunity for the relevant response procedures set out in the Flood Warning and Evacuation Plan to be invoked in response to receipt of a flood warning from the Environment Agency, thereby enabling flood risk to be mitigated in a timely manner. Figure 14: Environment Agency Flood Warning Areas Source: 2017 Level 1 SFRA – Appendix 13; Ref WHS 1459-T01-012 ©Weetwood 5135/FRA/Final/v1.012021-03-23 www.weetwood.net 14 Unit 1A, Botley Road, Oxford, OX2 0HD Flood Risk Assessment 6 SURFACE WATER MANAGEMENT The proposals include the change of one existing car parking bay to the front of the store to create a pedestrian access. The proposal is to replace the existing tarmac surface with block paving to differentiate the proposed pedestrianised area (circa 2.4 m x 4.8 m) from the adjacent car parking bays. There would be no change in the area of impermeable surfaces at the site and surface water runoff would continue to be managed by the existing surface water drainage system at the site. As such there is no requirement for any new surface water drainage to be introduced. ©Weetwood 5135/FRA/Final/v1.012021-03-23 www.weetwood.net 15 Unit 1A, Botley Road, Oxford, OX2 0HD Flood Risk Assessment 7 SUMMARY AND RECOMMENDATIONS This report has been prepared on behalf of Westminster Project Services Ltd and relates to the proposed changes to Unit 1a of the retail park off Botley Road, Oxford (the site). The proposals are for the construction of a 553 sq m mezzanine and modernisation of the shopfront, including a new freestanding signage feature on the shop front and minor works to the front of the store to reconfigure a very limited area of the car park to provide pedestrian access to the shop front. There is no change to the use of the site and the vulnerability to flood risk remains as existing (Less Vulnerable). The site is assessed to be at a Very Low risk of flooding from surface water and from reservoirs, canals, or other artificial sources. The principal source of flood risk at the site is from rivers, i.e., fluvial flood risk. According to the Flood Map for Planning the site is located within the outline of the present day 1 in 100 annual exceedance probability (AEP) event and is therefore defined by the NPPF as being situated within Flood Zone 3. An assessment of outputs from the 2018 hydraulic model of the Oxford reach of the River Thames and tributaries indicates that the site would be expected to flood to a depth of approximately 0.2 m during the present day 1 in 100 annal exceedance probability (AEP) event, increasing to 0.4 m during the present day 1 in 1,000 AEP event and 1 in 100 plus 35% climate change events. Maximum flood depths in the northern part of the car park and along Botley Road adjacent to the site are approximately 0.15 m and 0.25 m greater respectively. Regarding the proposals, there will be: • No increase in the area of impermeable surfaces at the site • No increase in surface water runoff rates. • No net increase in the built footprint of Unit 1a, • No reduction in flood storage at the site. As such the proposals will not increase on or off-site flood risk. A detailed assessment of flood risk at and in the vicinity of the site indicates that occupants and uses of the site will not be put at risk, subject to the implementation of a Flood Warning and Evacuation Plan prior to occupation of the reconfigured unit. Given the time taken for flooding to occur and for peak flood levels to be reached at and in the vicinity of the site, and because the site is located within a Flood Warning Area, the Flood Warning and Evacuation Plan would enable the site to be safely evacuated in advance of any flooding occurring. It is concluded that flood risk would be appropriately mitigated in accordance with planning policy (and specifically policy RE3), i.e., that the proposals would not increase flood risk on site or elsewhere, and that occupants of the site would not be put at risk. Given that there will be no increase in the area of impermeable surfaces at the site, surface water runoff would continue to be managed by the existing surface water drainage system at the site. ©Weetwood 5135/FRA/Final/v1.012021-03-23 www.weetwood.net 16 Unit 1A, Botley Road, Oxford, OX2 0HD Flood Risk Assessment Appendix A: Existing and Proposed Site ©Weetwood www.weetwood.net 17 5135/FRA/Final/v1.1/2021-03-23 This document is the property of the TILL JONES PARTNERSHIP Limited and copyright is reserved by them. No unauthorised copying, in whole or part or any form of reproduction is permitted. It must not be retained for reference and the contents may not be disclosed to any third party without the special written consent of the TILL JONES PARTNERSHIP Limited COPYRIGHT Figured dimensions must Only the latest revision of This Drawing is to be read be taken in preference this Drawing must be in conjunction with all to scaled. Do not scale used. If in doubt ask project drawings and from this drawing schedules issued to date CO- ORDINATION DIMENSIONS REVISIONS Any discrepancy must be notified to us in writing immediately IF IN DOUBT- ASK. The contractor any Sub-Contractor and Supplier will be deemed to have anticipated all costs and investigated all material availability prior to submission of offer.No claims will be entertained for failing to do so NOTE NORTH ORIENTATION 0 2 4 6 8 10 m SCALE 1:200 Fire Exit Fire Exit Fire Exit Fire Exit SCALE BAR Indicative location of Indicative amenity block. stair location. Final design and F'male Male Fire Final design layout TBC WC WC Exit and layout TBC Fire Landing Exit Staff Room Electric Electric Electric Electric Indicative Indicative lift location. lift location. Final design Final design Fire Exit Fire Exit and layout TBC and layout TBC Existing Unit Proposed Unit Proposed Unit Ground Floor GIA Ground Floor GIA Mezzanine Floor GIA 6,674 sqft / 620 sqm 6,674 sqft / 620 sqm 5,951 sqft / 553 sqm down up Access Floors GIA 590 sqft / 55 sqm Indicative line of mezzanine above up up down Indicative stair location. Final design and layout TBC Fire Exit Fire Exit Note, all dimensions shown are indicative based on recieved information. Site dimensions must be taken prior to any 3 4 3 3 4 3 3 3 4 3 3 4 3 3 manufacture Main Main Main Main entrance entrance entrance entrance Existing Ground Floor GA Plan Proposed Ground Floor GA Plan Proposed Mezzanine GA Plan 01 02 03 Scale 1:200 Scale 1:200 Scale 1:200 - --.--.------APP' DATE NOTE DRAWN BY BY REV' CLIENT LOGO Sofology CLIENT New Mezzanine in Existing Building PROJECT 1 Botley Road Oxford OX2 0HD ADDRESS SITE CODE POST 039 212 / JOB DRAWING NUMBER DRAWING REV' NUMBER Existing and Proposed GA Plans TITLE Planning DT CJ STATUS CHECKED DRAWING DRAWN BY BY 1:200 A1-LANDSCAPE 08.12.2020 SCALE SHEET SIZE DATE ARCHITECTS Company No. 12656856 4 Chestnut Court, Jill Lane, Sambourne, B96 6EW (t) 07498 839589 (e) [email protected] This document is the property of the TILL JONES PARTNERSHIP Limited and copyright is reserved by them. No unauthorised copying, in whole or part or any form of reproduction is permitted. It must not be retained for reference and the contents may not be disclosed to any third party without the special written consent of the TILL JONES PARTNERSHIP Limited COPYRIGHT Figured dimensions must Only the latest revision of This Drawing is to be read be taken in preference this Drawing must be in conjunction with all to scaled. Do not scale used. If in doubt ask project drawings and from this drawing schedules issued to date CO- ORDINATION DIMENSIONS REVISIONS Any discrepancy must be notified to us in writing immediately IF IN DOUBT- ASK. The contractor any Sub-Contractor and Supplier will be deemed to have anticipated all costs and investigated all material availability prior to submission of offer.No claims will be entertained for failing to do so NOTE 3 4 3 3 4 3 3 NORTH 5 5 5 5 5 3 ORIENTATION 1 Cladding 2 Brickwork 3 Aluminium Glazing 0 1000 2000 3000 4000 5000 mm 3 4 3 3 4 3 4 Automatic Doors SCALE 1:100 5 Bollards 6 RWP SCALE BAR 7 Indicative Steel Frame 8 Indicative Cross Bracing 5 5 Existing Part GA / Site Plan 01 Scale 1:100 7 1 1 1 1 1 8 8 3 6 4 3 3 4 3 1 3 4 2 7 5 5 6 6 Existing Section Existing Front Elevation 02 03 Scale 1:100 Scale 1:100 1 Cladding 2 Brickwork 3 Aluminium Glazing 4 Automatic Doors 5 Bollards Note, all dimensions shown are indicative based on recieved 6 RWP information. Site dimensions must be taken prior to any 7 Indicative Steel Frame manufacture 8 Indicative Cross Bracing New signage feature in front of existing building 9 Grey cladding to match existing 9 12 9 12 5 10 New steel frame to sign 12 11 Powder coated feature corner flashing's 12 Stainless steel bollards 13 Reconfigure car park to form new 13 Block paving to match existing pedestrian access to shop front and car 14 Kerbs to match existing parking layout. To include new kerbs 15 New thermoplastic paint to form new car park layout and block paving to match existing 14 14 13 5 14 Proposed Part GA / Site Plan 04 Scale 1:100 10826 New signage New signage feature in front of existing building feature in front of - --.--.------existing building 11 11 10 10 11 APP' DATE NOTE DRAWN BY BY Indicative signage zone subject to separate advertising REV' consent application by Tenant 9 Indicative signage zone subject to separate advertising 10 consent application CLIENT LOGO 10 by Tenant Sofology 9 10 CLIENT 11 11 New Signage Feature to Existing Building PROJECT 9 9 1 Botley Road Oxford OX2 0HD ADDRESS SITE CODE POST 9300 039 202 / JOB DRAWING NUMBER DRAWING REV' NUMBER Existing and Proposed Plan Elevation and Section TITLE Planning DT CJ STATUS CHECKED DRAWING DRAWN BY BY 12 12 12 12 1:100 A1-LANDSCAPE 21.11.2020 SCALE SHEET SIZE DATE Proposed Section Proposed Front Elevation 05 06 Scale 1:100 Scale 1:100 ARCHITECTS Company No. 12656856 4 Chestnut Court, Jill Lane, Sambourne, B96 6EW (t) 07498 839589 (e) [email protected] Delivering client focussed services from offices in Leeds, London and Mold Flood Risk Assessments Flood Consequences Assessments Surface Water Drainage Foul Water Drainage Environmental Impact Assessments River Realignment and Restoration Water Framework Directive Assessments Flood Defence Consent Applications Sequential, Justification and Exception Tests Utility Assessments Expert Witness and Planning Appeals Discharge of Planning Conditions www.weetwood.net