The depth of underground lines can vary from just a few inches beneath the surface, to more than 10 feet. Even everyday tools like shovels can cause serious damage if lines aren’t properly located prior to digging.

So, make sure that you or contractor you hire looks at all the possibilities.

1.- Some typical depths where you might find certain lines are:

– Cable or telephone lines: 1 foot or less

– Electricity:  2 – 3 feet

– Water: 2 – 4 feet

-Sewage: 2 – 6 feet

– Gas lines 1- 4 feet

In general, there is no standardized depth for buried utilities; they vary by state, zone (Residential – Non-Residential), and the builder’s compliance with the depth to be excavated.

For this reason, it is very important to verify where and at what depth the utilities are located before dig.

2.- Marking Color, according to Buried Service

Red: Power lines

Yellow: Gas line

Orange Communications – Cable

Blue Drinking water

Green Sewerage

Colored ground markings

3.- Reasons to Call Utility Marking Private Line Locator

Building a garden pond

Planting a tree

Digging yard to install a sewer trench.

Digging post holes for a fence

Digging foundations

Digging to install an irrigation system.

Laying conduit for exterior outlets or lights


Legally the depths of buried utilities are standardized, which vary from Residential – Commercial – Public Roads – Industrial, this regulation firstly varies from state to state and secondly is not complied with by the construction company.


it is of high importance before excavating, to scan the site and verify which buried utilities are found and at what depth.

Before You Dig. This handy site offers resources to help you avoid a disastrous and costly accident.