CartoConsult provided Zone of Visual Influence (ZVI) visibility analysis and mapping to help reliably inform and decide a preferred structure design option for a recent solar PV installation at the Port of Barry for Associated British Ports (ABP). The ZVI was part of a wider Landscape Visual Impact Assessment (LVIA) project.
Our client, ACLA, needed this high level visibility mapping and analysis to report the preferred option, landscape assessment and identify potential view points for photomontage/verified view production. Without using CartoConsult’s innovative digital GIS mapping services, the client would not have been able to report this reliably in their LVIA report.
There are clear benefits to using CartoConsult’s GIS approach:
- Quick turnaround (next day delivery)
- Clear design option decision-making
- Professional, high-quality visual mapping graphics
- Streamline view-point selection for photomontage/verified views
- Accurate statistics production
- Improved stakeholder confidence and engagement
- One GIS software package used, streamlining workflow and providing consistent output
- No Photoshop exercise required – data only for reliability
- Cost effective
A ZVI, is a graphical output of where an existing or proposed structure can theoretically be visible/not visible, across a bare earth terrain. A Digital Terrain Model (DTM – no canopy heights, only terrain) is used to provide the lie of the land (topography) and a point, line or polygon GIS feature is used to provide the location of the existing or proposed structure.
A DTM can be obtained in various formats. For this project, it was deemed that the Terrain50 OS OpenData (50m resolution grid product) was detailed enough for a high level landscape assessment study. For this project extent, a more detailed 1-5m resolution DTM grid was available, but this would need to have been purchased. This option and quotation was provided to the client.
Location of proposed site
The great thing about this project was that there were 2 options proposed. One with a tall tower and one without the tower. The Architect needed support in reliably informing which option was best, and what the visual impact would be on the surrounding area. As well as the usual private investor stakeholders, our client had to inform the public stakeholders on the project at a consultation event. It is sensitive area, not only in heritage terms, but in the fact there are people already living close to the site, as well as a well-used core path that surrounds the site boundary. So there was a lot to think about in terms of visual impact.
ABP and ACLA provided CartoConsult with the coordinates and heights of the 2 options. From this information, a GIS point ’feature class’ was produced that would hold the spatial location (a point on a map) and also the intelligent attribute information, in this case the height for each option (XYZ).
Using GIS software and Geoprocessing analysis tools, a raster visibility dataset was produced. This raster was symbolised using the unique attributes in the raster. In this case, the client had decided that they wanted to show the ‘visible’ areas in green. From the raster, which is a geographically correct dataset, the area of land that would be visible was calculated, directly from within the GIS.
Delivered to the client were:
- 2x PDF of Visibility Map (With and without Tower)
- Visibility statistics
- How many properties lie within the theoretically visible areas
For a no obligation ZTV quotation, please do not hesitate to contact CartoConsult:
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