GPR / Utility Mapping
Utility Surveying, also known as Utility Mapping, is used to identify cable routes and pipelines beneath the ground using a combination of non-invasive and non-destructive means to characterise sub-surface features.
Aspect Land & Hydrographic Surveys Ltd have been undertaking utility mapping for 10 years and we have adopted emerging technologies to ensure that we remain at the forefront of service provision.
With specialist equipment including Ground Penetrating Radar (GPR) and Electro-Magnetic Locators (EML) used to locate and position buried services, any features identified can be hard marked on the ground and shown accurately on digital plans.
With meticulous planning and attention to detail, we ensure all available information is recorded accurately, within the recognised limitations of sub-surface surveying, producing outputs to PAS 128 standard or equivalent.
PAS 128 provides a robust methodology for delivering utility surveys in the UK. It focuses on levels of accuracy – referred to as Survey Category Types – which can be specified when requiring a PAS 128 compliant underground utility survey. The categories range from D, desktop analysis to A, full survey including physical identification / inspection by excavation or trial pits.
PAS 128 Survey Category Type D Underground utility plotted from utility record data only (not detected by geophysical methods). |
PAS 128 Survey Category Type C Underground utility plotted from utility record data only, but with site reconnaissance to match utility record with physical utility street furniture as a best fit. |
PAS 128 Survey Category Type B Utility detected by geophysical methods (single or multiple) to obtain a horizontal position and/or vertical position. (Depth) |
PAS 128 Survey Category Type A Utility verified and positioned by physical identification. This may be by strategically positioned vacuum excavation, hand dug trail pitting or by visual inspection within a utility chamber |
Our surveyors have undergone industry standard training in Utility Mapping and utilise Robotic Total Stations and RTK GPS (cm accurate) positioning equipment when conducting the surveys.
We can undertake utility mapping surveys and topographic surveys simultaneously and can co-ordinate traffic management / road closures as required in such a way as to minimise disruption. Staff have security clearance to work on MOD sites and air-side on airport runways.
Following data capture, detailed analysis can be undertaken using post-processing software to optimise outputs to enhance confidence in project planning for clients. Deliverables include 2D & 3D vector outputs and can be overlaid with topographic survey information.
In addition to the services being individually referenced in a drawing legend, depth of burial of the feature can also be shown.
Underground utility mapping makes a significant contribution to the safety of the workforce and members of the public and to minimising project delays and utility damage, saving time and reducing damage costs. It also reduces the amount of intrusive investigation required and gives more comprehensive site coverage than invasive approaches.
As well as mapping utilities, GPR can be used for a number of inspection purposes, such as void detection, including location of tie-rods when undertaken on piers, concrete slab and thickness analysis, rebar mapping, buried object detection such as storage tanks or fuel bunkers and verification of as-built structures and foundations.
Applications
Pipeline & Cable Detection Surveys
Void Detection Surveys
CCTV Inspection Surveys & Reporting
Pipeline Route Tracing
Buried Object Detection
Verification of GIS Utility Plans