# Line Locating and Marking in Denver

Line locating puts the buried line on the surface: path, depth, and defect position, marked on the ground. It is what turns camera footage into a place you can dig, and what keeps a dig from hitting something else.

- Path and depth marked on the surface.
- Sonde and transmitter locating.
- Pinpoints the defect before excavation.
- Reduces the size of the hole you have to open.

## What Line Locating Is

A transmitter energizes the line, or a sonde travels inside it, and a receiver at the surface tracks the signal. Following that signal produces the horizontal path of the pipe and a depth reading at any point along it, which we paint or flag on the ground.

Combined with a camera inspection, this converts a defect at a distance measurement into a physical spot in the yard with a known depth, so an access pit can be opened exactly where it needs to be.

Public utility locating marks the utility-owned lines in the right of way. Private lines on your property, including your sewer lateral, are generally not covered by that service, which is why private locating exists.

- The horizontal path of the line across the property.
- Depth at any point along the run.
- Exact surface position of a defect found on camera.
- Where the line crosses hardscape, trees, or utilities.
- Suitable positions for access pits or a bore path.
- Whether the line follows the route the records claim.

## When Line Locating Is the Right Method

Locating is the right step before any excavation, before any trenchless access pit is placed, and before a bore path is designed. Digging without it means digging wide to find the pipe, which costs more than locating did.

It is also the right step when the line path is simply unknown, when property records are wrong or missing, when planning landscaping or a foundation near a line, and when symptoms suggest a problem but the line route is unclear.

It has limits. Non-conductive pipe with no tracer wire cannot be energized directly and needs a sonde run inside it, so a line that cannot be entered may not be locatable without further access work.

- Non-metallic pipe with no tracer wire and no internal access.
- Collapse blocking the sonde from reaching the target.
- Very deep lines at the edge of receiver range.
- Heavy signal interference from dense adjacent utilities.
- Rebar, metal decking, or slab conditions distorting the signal.

## How Locating and Marking Runs

1. **Choose the Signal Source** We either energize the line with a transmitter or run a sonde inside it, depending on pipe material and available access.
2. **Track the Path** The receiver follows the signal across the property, establishing the horizontal route of the line.
3. **Read Depth and Mark** Depth is read at meaningful points and the route plus defect position are painted or flagged on the ground.
4. **Plan the Dig** The marks become the plan: where to open a pit, how deep, and what has to be cleared on the way down.

## Disruption, Timeline, and Cost Drivers

Locating a residential line is typically under an hour, non-destructive, and leaves nothing behind but marks that fade.

Cost drivers are property size, pipe material and whether a sonde run is required, how much interference is present, depth, and whether locating is standalone or bundled with a camera inspection.

It is usually the cheapest line item on an excavation project and the one that most reduces the size of the hole, which is where the savings come back.

## Frequently asked questions

**When is line locating the right step?**

Before any excavation or access pit, before designing a bore path, and whenever the line path or depth is unknown or the records are unreliable.

**What limits locating?**

Non-metallic pipe with no tracer wire and no internal access, collapse blocking the sonde, extreme depth, or heavy interference from adjacent utilities.

**Is this the same as calling for utility locates?**

No. Public locating marks utility-owned lines in the right of way. Private lines on your property, including your sewer lateral, generally are not included.

**How accurate is the depth reading?**

Accurate enough to plan a dig, though soil conditions and interference affect it, which is why potholing is used to confirm critical crossings.

**Can you locate the exact spot of a defect?**

Yes, by running the camera to the defect and locating the sonde in the camera head from the surface.

## Related Methods and Services

- [Sewer Camera Inspection](https://www.denversewerandwater.com/methods/sewer-camera-inspection) Video inspection that identifies the defect, its depth, and its location.
- [Hydro Excavation](https://www.denversewerandwater.com/methods/hydro-excavation) Water and vacuum digging for safe exposure around live utilities.
- [Open Cut Excavation](https://www.denversewerandwater.com/methods/open-cut-excavation) Traditional trenching when the line has to be exposed and physically replaced.
- [Method Comparison and Cost Guide](https://www.denversewerandwater.com/methods/sewer-repair-method-comparison) Side by side comparison of every method, what drives cost, and what rules each out.

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Denver Sewer and Water is a privately owned, licensed and insured plumbing contractor. We are not affiliated with, endorsed by, or connected to Denver Water, the municipal water utility, or any government entity. To pay a municipal water bill or reach the public utility, visit denverwater.org.

Source: https://www.denversewerandwater.com/methods/line-locating-and-marking