Sewer locating connects a transmitter inside the pipe with a mark above ground. It helps map a route or finding, but it does not replace an 811 request before digging.
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NexGen Plumbing Services
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THE DIRECT ANSWER
Sewer locating uses a small transmitter, called a sonde, inside a camera head or locating tool. A technician moves a compatible receiver across the ground to find that signal and estimate the transmitter’s position and depth. [1] This can connect a camera finding to a place on the property or help trace part of a private sewer route. It does not locate every buried utility or give permission to excavate. In Oklahoma, a separate OKIE811 request is still required before digging. [2]
Key points
Camera distance and sonde position are different measurements that provide useful context together.
Depth is an estimate affected by signal, equipment, and site conditions.
A private sewer locate is not permission to dig and not a substitute for 811 markings.
Two ways a sewer may be located
Sonde locating
Line tracing
A small transmitter marks the current camera or tool position.
A signal is applied to a conductive line or trace wire to follow a longer route.
Useful for pinpointing a visible defect or pipe endpoint.
Useful for mapping an accessible route when the line can carry a trace signal.
The receiver is centered over one transmitted point.
The receiver follows a continuous signal path across the surface.
How a camera finding is marked above ground
Advance the camera
The operator moves the camera to the joint, root entry, break, or other observation that needs a surface position.
Activate the transmitter
RIDGID describes an in-line sonde in its SeeSnake systems that a hand-held locator can detect above ground. [1]
Sweep and center the signal
The locator operator approaches from more than one direction and interprets the receiver response rather than relying on a single pass.
Mark position and estimated depth
The surface mark is documented with the camera distance, access point, and the observation being located.
Why a locate is still an estimate
Transmitter frequency, receiver setup, battery condition, and operator technique.
Burial depth and the position of the sonde inside the pipe.
Metal structures, reinforcing steel, nearby utilities, and other signal interference.
A depth reading should be treated as an estimate and checked against plans, elevations, and safe excavation practices.
What to save from the locate
Photos of the surface mark and nearby fixed reference points.
Camera distance and direction from the access point.
Estimated depth and any interference noted by the locator.
The video frame or observation associated with the mark.
Date of the separate 811 request before excavation begins.
A receiver reading does not prove ownership, an easement boundary, pipe material, or exact legal depth. It also does not show whether the sewer is above or below another utility unless that facility is separately located and the relationship is exposed safely. The paint or flag is a planning aid, not a complete underground map.
If a repair depends on precise elevation or grade, the locate should be compared with available plans, cleanout elevations, camera distance, and field measurements. Excavation still has to follow the required tolerance-zone and safe-exposure practices rather than placing equipment directly on an estimated centerline.
[2]Homeowners: Roles and ResponsibilitiesOklahoma One-Call System, Inc.Supports: Oklahoma locate requests, the three-business-day notice, positive response, and the private-line locating boundary
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