Architects and designers
✔ Confirm site feasibility
✔ Identify service easements and setbacks
→ Inform designs without risking future conflicts
Underground Service Locating Survey
An underground services survey (or utility locating survey) identifies and maps buried infrastructure – like water pipes, sewer lines, electrical conduits, communication cables, stormwater drains and gas mains.
Before any design, excavation or construction activity, you need to understand what lies beneath your site. Locating underground services prevents utility strikes, supports safe construction and ensures compliance with worksite regulations.
In many cases, it's also a necessary input for engineering design, authority approvals or asset documentation.
Why locate underground services?
You can't afford to guess what's beneath your site. Underground service locating is essential for:
- Risk prevention – Reduce the chance of injury, service disruption or legal liability from utility strikes.
- Design certainty – Map underground constraints to avoid clashes with proposed infrastructure.
- Regulatory compliance – Meet duty-of-care obligations under state and national guidelines.
- Cost control – Avoid unexpected rerouting costs, delays and redesigns.
- Efficient project planning – Integrate verified underground data into your planning, setout or asset documentation.
While Dial Before You Dig (DBYD) is a useful first step, it doesn’t guarantee accuracy. It’s not a physical investigation. That’s why on-site verification through a qualified underground survey is essential.
Who needs feature and level surveys?
From early-stage design to on-the-ground excavation, underground service locating helps ensure safe and efficient work across sectors.
What does an underground services survey involve?
Locating buried services isn’t as simple as using a single tool or technology. In practice, it requires a combination of desktop research, on-ground scanning, interpretation and spatial surveying. Here’s how it works:
1. Records review
We start by assessing all the available information. This might include Dial Before You Dig (DBYD) responses, as-built drawings, previous survey plans and utility authority data. These documents provide initial guidance, but are often incomplete or outdated.
2. Service locating (field investigation)
Specialist technicians use detection equipment to identify underground services. This includes:
Electromagnetic Induction (EMI)
- Used to detect metallic or conductive services (like metal pipes or power cables).
- Applies a signal to a line (directly or via induction) and traces the response above ground.
- Limited in areas with significant electromagnetic interference or no conductive materials.
Ground Penetrating Radar (GPR)
- Used to detect non-metallic or non-conductive services (like polyethylene pipes or fibre optics).
- Sends radio waves into the ground and measures reflected signals to identify underground objects.
- Provides depth information but can be affected by soil type, moisture and surface clutter.
3. Survey and spatial recording
Once we've detected and marked services on the ground, a licensed surveyor records their locations using GNSS, total stations or laser scanning. This data is then drafted into digital outputs that align with your site base plan or coordinate system.
What data is delivered from underground services locating?
Landair’s underground service surveys provide data in formats that can be integrated into planning, design or construction workflows. Typical deliverables include the below.
We can add underground data to your broader feature and level, cadastral or as-built surveys for a unified output.
Service location plans (PDF and DWG)
Showing detected services with appropriate annotations and confidence levels.
Integrated existing conditions plans
Combining surface feature and underground data into one comprehensive dataset.
Annotated site photos
Showing key detection areas, marked to show service locations and support future verification.
Survey report or summary
Detailing the methods, equipment used, service conflicts and any detection limitations.
When should you locate underground services?
It’s best to conduct underground surveys before finalising design, before applying for permits or ahead of any excavation activity. That means:
- Before site surveys in construction
- During land development design and approvals
- Prior to excavation, trenching, or piling
- When verifying the location of existing utility infrastructure
- For detailed pipeline mapping and asset documentation
