Topographical surveys can be a complex business so we have written this article to help you have a greater understanding of what is required.
What Exactly is a Topographical Survey?
A topographical survey, or land survey, is defined as the detailed mapping and charting of features upon an area of land. Commonly referred to as a “topo”, this particular type of survey within a client-defined parcel of land establishes its topographic relief and records any visible boundaries whilst accurately detailing the position of natural and man-made features. In addition, a survey can graphically represent the surface land cover and document its present land use.
Why Commission a Topographical Survey?
Topographical surveys are tremendously important for land development schemes in addition to maintaining ongoing management and administration of land. Mapping an area of land with pinpoint accuracy provides the ability to visualise both the site and its existing layout in a plan format. Secondly, a topographical survey can ensure proposed projects are fully supported in terms of any future planning applications. Lastly, it aids with the proposed development being accurately located within the defined Area of Interest.
Who Typically Commissions A Topographical Survey?
Architects, civil engineers, property developers, planning consultants, transport planners, commercial surveyors, homeowners and many more.
What Features ‘Feature’ In A Topographical Survey?
A topographical survey can incorporate many geospatial facets, including for example the following:
- Spot heights
- Fence Lines
- Change in Surfaces
- Pylons and Overhead Power Lines
- Building Positions
- Ridges & Eaves of Neighbouring Properties
- Highway Markings
- Kerb positions
- Highway Assets (e.g. street furniture)
- Water features (e.g. lakes, ponds and watercourses)
- Vegetation (hedges, trees and bushes)
How Are Topographical Surveys Undertaken?
Typically, an experienced land surveyor moves through the defined Area of Interest in a methodical manner armed with the latest GPS and total station laser technology to capture highly accurate geospatial point data. The first task however for the surveyor is to establish a number of control points across the site as these act as referenced locations and are needed for when the survey equipment is repositioned in and around the Area of Interest (note that these points are critical as they permit the data to be correctly linked together).
GPS surveying equipment can also be deployed to locate and position fixed points within the parcel of land and these allow the surveyed area to be tied to the National Coordinate System – the most common coordinate system employed in topographical surveying in the UK being OSGB36 (for more information on Coordinate Systems in the UK please click here).
The surveyor next undertakes recording of positions and heights utilising a total station plus hand measuring devices and note taking where necessary. On occasions it can save time and therefore increase efficiency to set up a robotic total station serving as a base unit that is able to track a pole mounted prism being held by the surveyor. On return to the office all of the collected survey data is then inserted into the latest Computer Aided Design software – we highly recommend Autodesk. On completion of the data processing a survey plan can subsequently be drawn up. This drawing can then be supplied on paper or sent digitally via email as a PDF/DWG file.
What Type of Final Output Can A Topographical Survey Create?
Completed drawings are typically supplied from A3 up to A0 in paper size or more frequently provided as a digital file in PDF/DWG format enabling the end-user to view the survey on a computer that has been accurately represented to scale.
Do You Need a Professional Topographical Survey To Be Undertaken?
We are a Bristol based geotechnology company specialising in the acquisition, visualisation and analysis of both survey and mapping data.
Our office is located close to the M48 Old Severn Bridge and this allows us to cover all of Bristol, Bath and the Southwest with ease. We offer coverage anywhere along the M4/M5 corridors including London, South Wales and the Midlands. In addition we are able to carry out surveys further afield in the UK and happily welcome any enquiry.
If you need to hire a professional Land Surveyor to carry out a topographical survey (or if you wish to discuss how we can assist you with your next project) then please dont hesitate to get in touch with us today at Pinpoint Mapping.