Utility line locating is the process of identifying and labelling underground utilities. These include a multitude of subsurface services including: communications, electrical, gas, sewer, water and more.
Utility line locating is a necessary on-site practice to update and confirm the accuracy of existing drawings and plans that may be outdated. BC contracting laws state that any planned ground disturbance must be notified to utility providers through the BC One Call platform who then accumulate all available ‘current’ information on subsurface pipe, cable & duct installations, however this is not always complete and/or accurate enough to break ground safely.
Utilizing the latest geophysical detecting technologies, GeoScan are able to determine the accurate location and depth of these services, onsite, that may or may not be detailed within the specific BC One Call package.
GeoScan uses industry-leading Ground Penetrating Radar (GPR) and Electromagnetic (EM) equipment. Both are non-destructive technologies that provide real-time results, that are marked on-site allowing you to dig with confidence.
Results from GeoScan utility locator surveys are detailed in an informative work order that includes a 2D PDF sketch with subsequent information covered on each utility present.
GeoScan offers in addition to our general locate package (2D PDF sketch and work order) a Subsurface Utility Engineering (SUE) report that is compliant with CI/ASCE 38-02 standards. GPS/Total station data points are collected for the location and depth of confirmed underground and surface utility features, including unknowns and suspected abandoned lines. These data points are then incorporated into an engineering drawing using CAD software and accompanied by a concise, survey report.
SUE form a key aspect in the pre-design engineering phase of projected developments and is a useful method for maintaining up to date records of privatized facilities. The produced CAD files can then be utilized to design and plan the implementation of future utilities prior to any proposed ground disturbance.
Applications and Benefits of advanced utility locating
Industries that rely on underground utility confirmation and ground clearance include: environmental (for geotechnical drilling/monitoring purposes), construction ( including but not limited to: shoring, excavating/trenching, tunneling, piling) and real estate, e.g. for Underground Storage Tank [UST] detection in line with new environmental laws on purchasing/selling property.
- On site accuracy you can be confident in
- Quick and efficient survey process
- Experienced technicians
- Fast, detailed site drawing and report
- Non-destructive method
- Proven, tested results with 10 years of case studies
- Plastic and metallic targets
Ground Penetrating Radar
A GPR system consists of a transmitting antenna coupled with a receiving antenna. Electromagnetic waves emitted by the antenna penetrate the ground and reflect off objects below the surface. By measuring the travel time for the electromagnetic waves to travel through the ground, reflect off the target and return to the surface, an estimate of the shape, size, and depth of a target can be made.
Traditional utility locates are often conducted utilizing only EM technology, requiring the locator to push a metallic ‘tracer’ line through any non-metallic conduits. Often this is impossible or not practical to do so, and so these non-metallic lines are missed.
GPR can identify both metallic and non-metallic targets, a key quality that makes it an exceptional tool when locating the wide variety of underground utilities. Furthermore, GPR allows our technicians to locate potential abandoned or untraceable lines that may not be identifiable by surface features.
Electromagnetic Radiodetection Technicals
Electromagnetic (EM) radiodetection equipment allows our technicians to perform several different locating methods; conductive, inductive and passive. This allows for specific lines and utilities to be isolated. EM locating works by generating an electromagnetic field around the desired utility and then tracing out this signal. This type of tracing method can only be used on conductive materials such as ductile iron water piping. Tracer wires or duct rods can be pushed through non-conductive (e.g. PVC) conduits to allow for EM locating, this relies on available access points such as manholes, catch basins or clean outs.
Radiodetection receivers can identify live power or radio signals which can be used to locate underground power and communication lines. This is particularly useful on sites where there is no available access point to connect directly to these services.
When required, GeoScan can offer live video footage for internal pipe inspection and assessment using camera snakes. This service can identify areas of pipe breaks and blockages.