Project No Brent Cross, Cricklewood London, UK Phase 1A North RMA

Transcription

1 Project No Brent Cross, Cricklewood London, UK Phase 1A North RMA River Overshadowing Impact Study For Waterman Energy, Environment & Design 18 th November Report 2 Rel.3 1 of rep2v3.docx

2 Report Title Client: Brent Cross, Cricklewood Phase 1A North RMA River Overshadowing Impact Study Waterman Energy, Environment & Design Document No: rep2v2 Release: 2 Copy No: Status Draft Report For Client Review Report Date: 18 th November 2014 Holds: Name: Signature: Date: Prepared by: Miss N Glover Checked by: Mr P. Bertacche Approved by: Dr V. Buttgereit Distribution: Copy no. to Client Copy no. to BMT Records Previous History: Release Release No: Status: Date: rep2v1 1 Draft report for Internal Review rep2v2 2 Draft report for Internal Review rep3v1 1 Draft Report for Internal Review 7 th Nov th Nov th May Report 2 Rel.3 2 of rep2v3.docx

3 Project No Brent Cross, Cricklewood Phase 1A North RMA River Overshadowing Impact Study Contents 1. Introduction Background Site Description Requirements for Overshadowing Assessment Methodology Model Detail Overshadowing Analysis Results and Conclusions References Figures Report 2 Rel.3 3 of rep2v3.docx

4 EXECUTIVE SUMMARY BMT Fluid Mechanics Ltd. (BMT) has conducted a shading study to assess the impact of the Phase 1A North RMA Brent Cross development on overshadowing of the River Brent waterway. The study takes into account all bridge structures, River Brent bridges and plot developments which form part of the Phase 1A North masterplan and are deemed to be in close enough proximity to the waterway to be relevant to the shading study. The current study was carried out based on the principles set out within Site Layout and Planning for Daylight and Sunlight: A Guide to Good Practice, Building Research Establishment (2011), in order to derive the overshadowing impact of all relevant buildings, bridges and structures across the River Brent. According to BRE guidelines[2], the sun hours plots for the river are shown for the 21st of March. It was found that the areas of the river failing the two-hour sunlight criteria are located in proximity of the bridges as indicated in the Figures 3.1 to 3.6. According the BRE criteria, the overshadowing caused by the bridge structures as well as the existing and proposed surrounding buildings does not have an adverse impact on the sun light availability Report 2 Rel.3 4 of rep2v3.docx

5 Project No Brent Cross, Cricklewood Phase 1A North RMA River Overshadowing Impact Study 1. Introduction 1.1. Background This report summarises the results of a study commissioned by Waterman Energy, Environment & Design to provide an overshadowing impact assessment of the Phase 1A North RMA Brent Cross development on the River Brent waterway in support of a planning application Site Description Location / Surrounding Area The Brent Cross site is located in the London Borough of Barnet, as presented in Figure 3.1. As illustrated in Figures 3.2 and 3.3, the proposed development is split in two parts by the A406. The proposed development located north of the A406 includes the Brent Cross Shopping Centre and is bound by the A41 to the east and low-rise residential areas to the west and north. The proposed development south of the A406 is bound by Edgware Road to the west of the railway tracks, low-rise residential buildings to the south and southeast; and by the A41 to the east. Two configurations are considered in the current study: Phase 1A North within the Context of Interim Surrounds Phase 1A North within the Context of Maximum Height Parameters Masterplan Report 2 Rel.3 5 of rep2v3.docx

6 Existing Surrounds The shadow plot assessment was carried out for Phase 1A North within the context of interim surrounds. This will be referred to as the existing case. Existing site conditions comprise low and medium-rise residential and office buildings to the south of the A406. North of the A406, the existing site comprises the existing Brent Cross Shopping Centre and car parking spaces. The 3D model / site plan of baseline site conditions is presented in Figure Proposed Surrounds The assessment was also carried out for Phase 1A North within the context of maximum height parameter masterplan. This will be referred to as the proposed case. Key Phase 1A (North) infrastructure elements of relevance to the assessment are the following structures: River Brent realignment; Bridge structures Residential Plots 53 and 54 The 3D model / site plan of the proposed development is presented in Figure Requirements for Overshadowing Assessment This study provides a quantitative assessment of the overshadowing impact of the Brent Cross masterplan on the River Brent waterway. Results are presented in the form of contour plots which indicate the area of the river impacted by the masterplan and the number of hours of sunlight per day these areas receive. In addition a series of shadow plots which provide information on how the areas of shading change throughout the course of the day is also supplied. Although there are no specific criteria for river shading from an ecological perspective this study has been commissioned in conjunction with the technical report to be provided by MacGregor Smith to provide a qualitative impact assessment of shading on the river corridor vegetation and ecology Report 2 Rel.3 6 of rep2v3.docx

7 2. Methodology 2.1. Model Detail Computational numerical models were constructed to represent the site conditions including the proposed development. The models included a detailed representation of adjacent buildings up to a distance judged to have an influence on the availability of natural light. The model of the proposed development was constructed based on a 3D CAD model and drawings supplied by Waterman Energy, Environment and Design as follows: Drawing Date 904_BXCricklewoodSitePlan_Phase1AN_3DView.dwg 03 September _BXC_Buildings_Maxpara.dwg 15 October Overshadowing Analysis Based on the 3-D model created from the information above a numerical simulation was carried out to determine the areas of the River Brent affected by overshadowing and the hours of sunlight per day received in these areas. Sunlight hours and shading plots were calculated by simulating the movement of sun for each hour of the day using accurate sun paths for the geographical coordinates of the site Report 2 Rel.3 7 of rep2v3.docx

8 3. Results and Conclusions The current study was carried out based on the principles set out within Site Layout and Planning for Daylight and Sunlight: A Guide to Good Practice, Building Research Establishment (2011), in order to derive the overshadowing impact of all relevant buildings, bridges and structures across the River Brent. According to BRE guidelines [2], the sun hours plots for the river are shown for the 21 st of March. Figure 3.1 and Figure 3.4 shows the sun-hours plots for both the existing (i.e. interim surrounds) and the proposed (i.e. maximum height parameters masterplan). The contour areas in pink indicate the areas of the river which receive less than two hours of sunlight on the 21 st of March. Full details of the number of hours of sunlight received at various monitoring points across the river can be found in electronic appendix A. According to the BRE criteria at least 50% of the area of any outdoor amenity space should receive at least 2 hours of sunlight on the 21 st March. According to this criteria the proposed bridge structures and surrounding buildings do not have an adverse impact on the sun light availability to the waterway. Shadow plots for the months of March, June, September and December are given for both the interim surrounds case and the maximum parameters case in Figures Shadow plot animations can be found in electronic appendix B Report 2 Rel.3 8 of rep2v3.docx

9 4. References [1] BS :2008, Lighting for buildings Part 2: Code of practice for daylighting., [2] Building Research Establishment Report, Site Layout Planning for Daylight and Sunlight: A Guide to Good Practice, P. Littlefair, Second Edition, Report 2 Rel.3 9 of rep2v3.docx

10 5. Figures Figure 1.1: Site Layout and Assessment Area (outlined in red) Western River Brent Alteration & Diversion Works River Brent Bridges Bridge Structure B6 (M1 Junction Pedestrian & Cycle Bridge) River Brent Bridges Bridge Structure B1 (Replacement A406 Templehof Bridge) Brent Cross Shopping Centre Eastern River Brent River Brent Car Park Alteration & Diversion Works Bridges Central River Brent Alteration & Diversion Works Bridge Structure B7 (Living Bridge) Claremont Park Improvements Clitterhouse Playing Fields Improvements Part Brent Cross Phase 1A North Site Plan Drawing no.: FIG 1 Status: Preliminary By: S Mijorski Date: 18-Nov-14 Figure 1.2: 3-D model of Existing Scheme Brent Cross Phase 1A North 3-D model of Existing Scheme Drawing no.: FIG 2 Status: Preliminary By: S Mijorski Date: 18-Nov Report 2 Rel.3 10 of rep2v3.docx

11 Figure 1.3: 3-D model of Proposed Scheme Brent Cross Phase 1A North 3-D model of Proposed Scheme Drawing no.: FIG 3 Status: Preliminary By: S Mijorski Date: 18-Nov Report 2 Rel.3 11 of rep2v3.docx

12 Figure 3.1: Areas of the River Brent Affected by Overshadowing and Hours of Sunlight Available per Day Existing Scheme Brent Cross Phase 1A North Brent River Existing Scheme Drawing no.: FIG 4 Status: Preliminary By: S Mijorski Date: 18-Nov-14 Figure 3.2: Areas of the River Brent Affected by Overshadowing and Hours of Sunlight Available per Day - Existing Scheme, West Close up Existing Scheme Brent River Two hour sun contour Failing areas Brent Cross Phase 1A North Brent River Existing Scheme, Close Up Drawing no.: FIG 5 Status: Preliminary By: S Mijorski Date: 18-Nov Report 2 Rel.3 12 of rep2v3.docx

13 Figure 3.3: Areas of the River Brent Affected by Overshadowing and Hours of Sunlight Available per Day - Existing Scheme, East Close up Existing Scheme Brent River Two hour sun contour Failing areas Brent Cross Phase 1A North Brent River Existing Scheme, Close Up Drawing no.: FIG 6 Status: Preliminary By: S Mijorski Date: 18-Nov-14 Figure 3.4: Areas of the River Brent Affected by Overshadowing and Hours of Sunlight Available per Day - Proposed Scheme Brent Cross Phase 1A North Brent River Proposed Scheme Drawing no.: FIG 7 Status: Preliminary By: S Mijorski Date: 18-Nov Report 2 Rel.3 13 of rep2v3.docx

14 Figure 3.5: Areas of the River Brent Affected by Overshadowing and Hours of Sunlight Available per Day - Proposed Scheme, West Close up Proposed Scheme Brent River Two hour sun contour Failing areas Brent Cross Phase 1A North Brent River Proposed Scheme, Close Up Drawing no.: FIG 8 Status: Preliminary By: S Mijorski Date: 18-Nov-14 Figure 3.6: Areas of the River Brent Affected by Overshadowing and Hours of Sunlight Available per Day - Proposed Scheme, West Close up Proposed Scheme Brent River Two hour sun contour Failing areas Brent Cross Phase 1A North Brent River Proposed Scheme, Close Up Drawing no.: FIG 9 Status: Preliminary By: S Mijorski Date: 18-Nov Report 2 Rel.3 14 of rep2v3.docx

15 3pm 12pm 9am BMT Fluid Mechanics Limited Figure 3.7: Shadow Plots 21 st March Existing Scheme West Brent River Section Central Brent River Section East Brent River Section Report 2 Rel.3 15 of rep2v3.docx

16 3pm 12pm 9am BMT Fluid Mechanics Limited Figure 3.8: Shadow Plots 21 st March Proposed Scheme West Brent River Section Central Brent River Section East Brent River Section Report 2 Rel.3 16 of rep2v3.docx

17 3pm 12pm 9am BMT Fluid Mechanics Limited Figure 3.9: Shadow Plots 21 st June Existing Scheme West Brent River Section Central Brent River Section East Brent River Section Report 2 Rel.3 17 of rep2v3.docx

18 3pm 12pm 9am BMT Fluid Mechanics Limited Figure 3.10: Shadow Plots 21 st June Proposed Scheme West Brent River Section Central Brent River Section East Brent River Section Report 2 Rel.3 18 of rep2v3.docx

19 3pm 12pm 9am BMT Fluid Mechanics Limited Figure 3.11: Shadow Plots 21 st September Existing Scheme West Brent River Section Central Brent River Section East Brent River Section Report 2 Rel.3 19 of rep2v3.docx

20 3pm 12pm 9am BMT Fluid Mechanics Limited Figure 3.12: Shadow Plots 21 st September Proposed Scheme West Brent River Section Central Brent River Section East Brent River Section Report 2 Rel.3 20 of rep2v3.docx

21 3pm 12pm 9am BMT Fluid Mechanics Limited Figure 3.13: Shadow Plots 21 st December Existing Scheme West Brent River Section Central Brent River Section East Brent River Section Report 2 Rel.3 21 of rep2v3.docx

22 3pm 12pm 9am BMT Fluid Mechanics Limited Figure 3.14: Shadow Plots 21 st December Proposed Scheme West Brent River Section Central Brent River Section East Brent River Section Report 2 Rel.3 22 of rep2v3.docx

23 APPENDIX A. 2 HOUR SUNLIGHT CONTOUR PLOT The number of sun hours for all the monitoring points defined on the river sections are provided in electronic form in AutoCad dwg format in the following files: Interim Surrounds Brent_Cross_Existing Surrounding Scheme.dwg Maximum Height Parameter Masterplan Brent_Cross_Proposed Surrounding Scheme.dwg APPENDIX B. SHADOW ANIMATIONS Detailed information regarding the shadow plots are provided in the following electronic appendices: Appendix - Shadow Plots.zip This provides shadow plot animations in the form of html files and jpg files detailing shadow plots at various times of the day Report 2 Rel.3 23 of 2