Sonde Locating for Non-Metallic Pipe & Drains Across BC
Trace and depth non-metallic drains, sewers and ducts using an in-pipe sonde transmitter
About This Service
Non-metallic drains, sewers, PVC conduit and clay pipe carry no electrical signal — so a standard EM locator cannot trace them. A sonde (a small battery-powered transmitter) is pushed or floated into the pipe on a camera head or push-rod, broadcasting a precise signal the EM receiver tracks from the surface. This is the definitive method for mapping the route and depth of a non-metallic drain or duct, and it pairs naturally with CCTV inspection so a defect can be located on the surface the moment it is seen on camera.
How It Works
- 1
A sonde transmitter is attached to a CCTV camera head or push-rod and inserted into the pipe.
- 2
The sonde broadcasts a fixed frequency from its position inside the pipe.
- 3
An EM receiver above ground pinpoints the sonde's horizontal position and measures its depth.
- 4
As the camera advances, each feature or defect is located and marked on the surface.
- 5
The full route, depth profile and any defect positions are recorded on a sketch or plan.
When It's Used
What You Receive
- Surface marking of the pipe route and key features
- Depth measurement at the defect or access point
- Coordinated CCTV + sonde locate (defect position on surface)
- Route sketch with depth profile
- Excavation advisory for targeted dig
Sonde & Drain Locating — BC Locations
Available across all of British Columbia.
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Need non-metallic pipe, concrete or void imaging too? Explore GPR scanning →
Frequently asked questions
When do you use a sonde instead of standard EM locating?
A sonde is required whenever the target pipe is non-metallic and has no tracer wire — PVC, HDPE, clay or concrete drains. The sonde provides the signal from inside that the pipe itself cannot carry.
Can you locate exactly where a drain is collapsed or blocked?
Yes. We run the CCTV camera to the defect, stop at the collapse or blockage, and locate the sonde at the camera head from the surface — marking the precise dig point and depth for a spot repair instead of trenching the whole line.
How deep can a sonde be located?
Standard sondes locate reliably to several metres depending on the frequency and soil. Deeper drains require a lower-frequency sonde; we select the right unit for the expected depth.
Sonde & Drain Locating Across British Columbia
LeakInspections.ca is a division of Anyleak.ca and part of the Leak.ca family — BC's subsurface locating and leak detection specialists since 1999.