Review of Environmental Sensitivity in Oxfordshire
Total Page:16
File Type:pdf, Size:1020Kb
Review of Environmental Sensitivity in Oxfordshire Final Report – Update Prepared by LUC August 2016 Planning & EIA LUC BRISTOL Offices also in: Land Use Consultants Ltd th Registered in England Design 12 Floor Colston Tower London Registered number: 2549296 Landscape Planning Colston Street Bristol Glasgow Registered Office: Landscape Management BS1 4XE Edinburgh 43 Chalton Street Ecology T +44 (0)117 929 1997 London NW1 1JD Mapping & Visualisation [email protected] FS 566056 EMS 566057 LUC uses 100% recycled paper Contents 1 Introduction 1 2 Methodology 3 Classification of environmental data 3 Assessment of environmental sensitivity 3 Mapping of data 4 3 Themes 6 Biodiversity and Geodiversity Assets 6 Landscape/Visual Assets 6 Archaeology/Heritage Assets 7 Community and Green Space Assets 7 Land Use Assets 7 Water Assets 7 Public Access Assets 8 4 Overall sensitivity mapping 23 5 Next steps 28 Utilisation of the data 28 Opportunities for improved protection and enhancement 28 Potential improvements to the method 29 Appendix 1 31 Sensitivity scoring table 31 Version Date Version Details Prepared by Checked by Approved by 3 04/08/2016 Final report Maria Grant Taran Livingston Taran Livingston Robert Deane Joe Nunn 1 Introduction 1.1 This short report describes and summarises the results of a mapping exercise to collate and analyse digitised data that Oxfordshire County Council (OCC) holds on a range of environmental assets within the county of Oxfordshire. The study has sought to establish the pattern of environmental assets and their sensitivity to change as a source of internal evidence for County Council staff to use when considering potential land use change. It follows an earlier pilot study that followed the same process for the Oxfordshire Knowledge Spine and Oxford Green Belt. 1.2 This report was originally produced in May 2015, and has been updated to reflect more recent environmental datasets obtained by OCC, particularly in respect of areas of priority habitat. The methodology has not changed, but the figures have been updated as relevant to reflect the more recent datasets (these are highlighted in Chapter 3). Limitations of the study 1.3 The purpose of this exercise is to provide a strategic, ‘broad-brush’ approach to identify concentrations of greatest known environmental sensitivity to change. It does not seek to be a definitive or comprehensive guide to the location of all environmental assets or the specific threats that face them. 1.4 In this context, it should be noted that ‘white’ areas on the map (where there are no assets shown) are not necessarily devoid of environmental or heritage interest. The results of this study are not a replacement for standard planning protocol and the evidence studies undertaken by local planning authorities to inform Local Plans, and its limitations should be recognised. The study area 1.5 The study area covers the whole of the county of Oxfordshire, extending the analysis of data previously undertaken for the pilot area in the Knowledge Spine and Green Belt. The study area is illustrated in Figure 1. However, it should be noted that while the study area stops at the County boundary, many of the environmental assets often continue over the boundary, and their sensitivities therefore extend beyond the boundary. Structure of the report 1.6 This report is set out as follows: Chapter 2 – Sets out the methodology used in scoring the sensitivity of the environmental assets. Chapter 3 – Provides a breakdown of the environmental asset themes and the associated asset and sensitivity maps for each theme. Chapter 4 – Presents the overall sensitivity mapping for all environmental assets, including a map identifying areas of highest sensitivity. Chapter 5 – Advises on how to use the outputs of this project, and potential improvements that could be made if resources were available. Review of Environmental Sensitivity in Oxfordshire 1 August 2016 Update Contains Ordnance Survey data © Crown copyright and database right 2016 Cherwell District West Oxfordshire District Oxford City Vale of South White Horse Oxfordshire District District 0 5 10 E km Oxfordshire County Review of Environmental District Boundary Sensitivity in Oxfordshire Figure 1: Study Area Map Scale @ A3: 1:250,000 CB: EB:nunn_j LUCGLA 6705_001_r4_All_Figs_A3P 14/07/2016 2 Methodology Classification of environmental data 2.1 Following the receipt of the relevant data under licence from the County Council, the datasets for the environmental assets (which are described in the next chapter) were grouped into seven themes as follows: Biodiversity and Geodiversity Assets. Landscape and Visual Assets. Archaeology and Heritage Assets. Community and Green Space Assets. Land Use Assets. Water Assets. Public Access Assets. Assessment of environmental sensitivity 2.2 It was important that the approach taken to identifying the assets that are most sensitive to future change allows a consistent approach to be taken across all the themes but is also sophisticated enough to measure both the significance of the asset (either nationally or locally important) and also its capacity to withstand change (either susceptible or robust). 2.3 The scale of importance was scored according to the following criteria: National importance - The asset is considered to be of national or international importance, as recognised by statutory designations or national policy. Local importance - The asset does not qualify as being nationally important, but is considered to have local importance. 2.4 The vulnerability to change assessment takes two factors into account. The first is the fragility of the environmental asset to change which would damage its condition and value (in terms of the benefits it is providing). This fragility may depend on the scale of the asset and the extent to which threats affecting part of the asset would affect its overall integrity (i.e. landscape-scale assets being potentially less fragile than smaller sites). The assessment of fragility does not take account of the impact of protection from planning policy but does consider specific statutory protection from legal designations. Socio-economic factors such as the ownership and management of assets (at both local and national level) are considered where such management seeks to control the drivers of environmental change. The second is the recoverability of the asset - i.e. the extent to which its condition and value would regenerate after damage takes place. 2.5 The two scores from this assessment may be as follows: Robust - The asset is not particularly fragile (i.e. it could withstand a moderate level of disruption from the anticipated threats before suffering significant harm OR (if it is fragile), the asset is likely to regenerate strongly within a reasonable period (e.g. 5-10 years) after the disruption from the threat has taken place). Susceptible - The asset is fragile and would not be expected to recover within a reasonable period OR (if the asset is not fragile), recovery from any harm caused would be slow or would not take place at all (i.e. the damage would be irreversible). Review of Environmental Sensitivity in Oxfordshire 3 August 2016 Update 2.6 The overall sensitivity score for each asset type is assigned automatically, based on the scores for the scale of importance and vulnerability to change as in the matrix illustrated in Table 1, giving a score of Higher Sensitivity, Moderate Sensitivity or Lesser Sensitivity. Table 1. Proposed classification of sensitivity values Level of significance Nationally significant Locally significant Capacity Susceptible Higher sensitivity Moderate sensitivity to (Low capacity) withstand Robust Moderate sensitivity Lower sensitivity change (High capacity) 2.7 In addition, a confidence score was given to each of the assets based on quality of the data, the variability of the sites within the dataset and ultimately the certainty of the judgement made. Score of 1 – High confidence in sensitivity value given – the evidence for link is strong and variability in the characteristics of the sites is low. Score of 2 – Medium confidence in sensitivity value given - some doubt over reliability of the judgement made and/or moderate level of variability in characteristics of sites. Score of 3 - Low confidence in sensitivity value given - Uncertainty over reliability of the judgement made and/or high level of variability in characteristics of sites. 2.8 The confidence score is provided for information. It was not used to calculate the sensitivity values (above). 2.9 Notes were also added to the table to justify the reasoning behind the scoring given. Mapping of data 2.10 The Ordnance Survey 1:250,000 greyscale raster was chosen as the base for the maps shown in this report since this gives an appropriate level of detail of the County when viewed at either A3 or A4 scale. 2.11 The spatial data was mapped out in three main stages as described below. 1. Vector maps showing each of the environmental assets 2.12 Firstly, the location of the environmental assets was mapped in vector format (accurately showing the site boundaries, where relevant to the dataset), with one map for each of the seven themes and all the assets in each theme being shown on the appropriate theme map. 2. Rasterised maps showing the patterns of environmental sensitivity for each theme 2.13 Secondly, a map was produced for each of the themes showing the pattern of environmental sensitivity arising from the assets in that theme. To do this the vector data for each of the environmental assets was converted to raster data using a grid 50m by 50m1, ensuring that small and linear sites (such as Scheduled Monuments and public rights of way) were ‘visible’ in the sensitivity scoring, while still preserving fine detail on the map. 2.14 The sensitivity scores were applied to each of the raster layers and these layers were then combined for each theme, producing an overall sensitivity map for that theme.