Topographical & GPR Surveys

Topographical and Ground Penetrating Radar Surveys

Typically, these surveys are carried out prior to any intrusive investigation as they provide the base information to allow intrusive investigations to proceed with an acceptable level of safety.

Topographical Survey

A topographical survey, or land survey as it also known is an accurate way to gather spatial data about the natural and manmade features of an area.  Our surveys can provide detailed information to identify and map ground contours and gather spot heights; determine the location, size and dimensions of the natural and manmade features of the land such as trees, lakes, streams, buildings, and fences.  We work with our clients to ensure the best type of survey to suit your needs depending on the scale of the map required, location (urban or rural), accuracy and levels.

There are multiple uses of topographical surveys, such as those listed below:

• Shows details of properties, land features and physical boundaries.
• Provide engineers detail information about the site and project they are working such as: borehole coordinates and elevations.
• Can aid designer, architects, planners, and engineers in the early stages of a project’s design and planning.

Topographical surveys can also be conducted on large bodies of water, known as bathymetric surveys, these can be used to map the bottom rivers, lakes and even the ocean. Useful for future of green energy in offshore wind farm development sites and hydroelectric dams!

We can present our topographical surveys in multiple formats subject to client requirements.  Typical examples are submission for the Land Registry, which require specific scales and outputs for compliance. However, our surveys can be delivered in both 2D and 3D formats as digital files and 3D data can also be presented in Revit.

Ground Penetrating Radar Survey

Within a Ground Penetrating Radar (GPR) survey, utility desktop studies can be carried out to locate the general location of known utilities and services.  This requires obtaining drawings and maps of known services in the area from the relevant asset’s owner.

This will dictate whether a further site study should be completed.  These surveys entail making use of high frequency radio wave pulses to image the ground’s sub-surface. GPR can have multiple applications within soil, rock, ice, water, pavements, and structures.  In the right conditions, GPR can detect:

• subsurface objects such as: boulders, cables, and pipes.
• changes in material properties such as: density.
• voids and cracks.
• Changes in soil density associated with some forms of contamination.

Once known utilities and services have been mapped and found the final step is to do an intrusive investigation to uncover the marked known and unknown services in the study area.  Using insulated hand excavation tools and safe digging methods and procedure, assets are uncovered and detailed, with findings being photographed and recorded.

The above process also encompasses an entire PAS 128 utility survey from type D – A. PAS 128 surveys are not compulsory when working on, near and around services, however, they do make life easier.

The typical surveying processes includes:

1. Gathering general information e.g., geographical area of site, level of detail required, accuracy and data output format
2. Planning of time scale and pricing
3. Onsite surveys, being individuals or groups of surveyors
4. Data processing and preparation of survey output
5. Internal quality assurance by senior staff to approve final outputs
6. Delivery of final survey to the client

The time scale for producing the survey report depends on the size of the area covered and the complexity of surveying required, all works schedules are organised with the client to ensure everyone’s needs are met.

GES can provide the most cost and time effective solutions to our clients for surveys of varying sizes to meet your requirements.