BYDA records are a starting point — not a guarantee. When plans are missing, incomplete, or decades old, GPR and electromagnetic induction detects what's actually in the ground.
NULCA certified. AS5488 compliant. Results documented and ready for your project.
Relying solely on BYDA records is a common source of utility strikes. Understanding why records fail helps project teams set the right expectations before they break ground.
Services installed in the 1960s–1990s were often documented on paper plans that were never digitised or updated when services were added.
Extensions, sub-metering, irrigation lines, and private communications cables are rarely lodged with utility authorities.
When roads or buildings change, services are often rerouted — but the as-built update doesn't always make it back to the records.
BYDA records depend on asset owners registering their infrastructure. Smaller utilities, councils, and private assets are commonly missing.
A utility strike is rarely just a line item on an insurance claim. The consequences cascade: project shutdown, emergency response, redesigns, schedule delays, and liability exposure that can outlast the project itself.
Under WHS legislation, principal contractors and excavation operators have a duty to take all reasonably practicable steps to identify underground services before commencing ground-disturbing works. A detection survey at QL-B is generally considered the minimum standard for construction-phase excavation.
The cost of a pre-dig locate is a fraction of the cost of a single strike — and a fraction of the cost of the documentation needed to defend a claim after one.
Two core technologies, used in combination, cover the full range of buried service types — metallic and non-metallic alike.
A signal is applied to a conductive service — either directly or inductively — and traced along its path. This method is highly effective for metallic pipes and cables and can detect active energised services passively without any physical connection.
Best for: metallic water mains, gas pipes, power cables, communications.
Radio pulses are transmitted into the ground and reflections are read to build a cross-sectional image of buried objects. GPR detects non-metallic pipes, conduits, and voids that EMI cannot reach.
Best for: PVC and HDPE pipes, concrete ducts, subsurface voids, service corridors.
Where services are physically located and marked, survey-grade positioning can be applied to produce an AS5488 QL-B or QL-A plan — a georeferenced map of detected services in CAD or GIS format, ready for direct integration with your design or construction documentation. Learn more: AS5488 Quality Level Guide 2026 →
Australian Standard AS5488 classifies subsurface utility information into four quality levels. The right level depends on project risk, proximity to critical assets, and stage of works.
BYDA and utility authority plans reviewed. No field work. Suitable only for early planning.
Surface features and exposed assets surveyed. Existing service records correlated with site conditions.
GPR and electromagnetic induction used to locate and mark services. Positions recorded to survey. Most pre-excavation projects reach QL-B.
Most common for pre-excavation works
Physical exposure of services to confirm type, size, condition, and exact position. Required for high-risk excavation near critical assets.
Source: AS5488 Quality Level Guide →
Documented results your project team can rely on.
Services marked on the ground surface with paint or stakes — clear, colour-coded, and tied to your site datum.
CAD or GIS plan showing detected service positions, depths, and type — ready for your design team.
Written documentation of detection methods used, area covered, confidence levels, and any limitations noted.
Need integrated survey plans? Contact HR Utilities — as part of the HR Surveyors group, locating and survey-grade deliverables can be combined in a single workflow.
BYDA (Before You Dig Australia) provides design records from utility asset owners — these reflect what was installed, not necessarily what's in the ground today. Services may have been relocated, added by private parties, or never registered. GPR and electromagnetic induction physically detect what's actually present at the time of survey, regardless of whether it appears in BYDA records.
Yes, with limitations. Electromagnetic induction requires a conductive signal path, which non-metallic pipes (PVC, HDPE) don't provide. For these services, we use Ground Penetrating Radar (GPR), which detects the pipe material itself. In some cases, a traceable copper rod can be inserted and traced. Our technicians select the right combination of methods based on what's known about the site.
A nil-find result is still a documented result. We provide a written report noting what detection methods were used, the area covered, and that no services were detected at the specified quality level. This gives your project team a defensible record that due diligence was performed before excavation.
For standard projects across Melbourne and Geelong, we typically mobilise within 1–3 business days of confirmed booking. For urgent pre-excavation requirements, contact our team directly to discuss availability. We operate from offices in Huntingdale (Melbourne), Geelong, and West Leederville (Perth).
Expert utility locating services with BYDA certified precision.
Serving projects across Australia with advanced subsurface mapping solutions.