- GeoData
- » Viewshed
GIS Viewshed Analysis to Identify Zones of Potential Visual Impact on Protected Landscapes
A Natural England project
Natural England have commissioned a project to create a GIS map to identify zones of potential visual impact on protected landscapes. The GeoData Institute, University of Southampton were contracted to undertake this work and we are keen to get your comments on the results we have produced.
Each National Park Authority, AONB Partnership, Heritage Coast and National Trail will be given time to consider the mapped output of the analysis and to identify and record issues or comments on the map for their NP/AONB. Natural England will use the final GIS datasets to support its screening of development proposals potentially affecting protected landscapes. The interpretation and use of the data by NE will be guided by feedback received during the consultation.
A full description of the methodology is provided in the early part of this report.
However, in brief, we took a digital terrain model and used GIS terrain analysis software to identify which parts of the surrounding landscape are visible from protected areas and which are not. In addition, for the non-visible zones, we calculated the Height at which Objects would Become Visible (HOBV) from the protected area if they were to be built in this zone. The idea is that users will be able to overlay this map with planning application locations, either XY coordinates or 'as-built' building footprints.
The Maps
The outputs are provided in a variety of formats for you to view.
- ESRI GeoDatabase (v 9.3)
- MapInfo Tab file (*.tab)
- Raster grid 10m resolution (maps available to 5m in final product)
- KML
- PDF (GeoPDF).
We have also provided a predefined legend (10m bands) where zero (0m) represents areas already currently visible from the protected landscape and shown as transparent. However, we are still working on the final format and symbology for the layer NE will release. For those of you using the raster version in your own GIS, you will have the flexibility to change the classes.
How to provide feedback
We wish to gather feedback in 2 ways.
Location specific comments
We are keen that the comments on the maps are geographically tagged to the area to which they relate. This will either involve marking up the file itself or editing a predefined GIS template (polygon layer). Specific instructions are provided for each format. However, PLEASE ONLY MAKE COMMENTS INTO 1 OF THE FORMATS.
We are seeking comments based on your local knowledge and experience of the areas and while we do not wish to be too prescriptive about this, we are keen to gain your views on the following:
- Are there any areas where you think the map is wrong and if so why?
- Are there particularly sensitive areas?
- Any other location specific comments about the data?
General Comments
We are also seeking more general comments which will be gathered via a short online questionnaire:
- Overall, does the map look right for your area?
- How do you think you might use the data?
- Format and presentation (symbology) of the data for delivery to you
- Any other general comments
We are mainly interested in your views on the protected landscapes for which you have responsibility. However, if you wish to make comments about abutting protected areas or overlapping trails, then please do so, in a seperate file.
If you have any queries or are having any technical difficulties, please contact:
» viewshed@geodata.soton.ac.uk
We also have FAQs.
Many thanks for your time,
Andy Murdock
GIS Manager, GeoData Institute, University of Southampton
apm@geodata.soton.ac.uk, Tel. 023 8059 2719
