Underground Utility Locating – What Do the Colors Mean?

May 25, 2017

 gas line locating

You’ve made the right decision when you decided to have the public or private utilities marked before digging or excavating on your construction project. After the locator does his/her work, there are some nice colors identifying those utility lines you had marked, but you’re left wondering, “What do these colors mean?”

At Penhall Technologies, when we perform a underground utility locate or pipe locating services, it is protocol for our analysts to leave behind a form that explains all markings, and what each utility line color marking means. The colors used follow the guidelines set by the American Public Works Association (APWA).

What is the APWA?

As the voice for public works, and also private sectors providing supplies and services in public works, the APWA is a comprehensive resource that, among other guidelines, put into place a color guideline for all utility locate markings. These guidelines have become a national standard to keep us all in the utility locating industry on the same page. This is an effort that keeps all construction sites, whether commercial or residential, safer for everyone.

To give a background and rationale, the APWA states the importance of these guidelines.

“The APWA, through its Utilities and Public Right of Way Committee, has developed and published guidelines for temporary marking of underground utilities which include an APWA Uniform Color Code in order to minimize damages during excavation and similar operations in which the earth or the earth’s surface is moved, removed, or displaced.”

Source: http://www.apwa.net/library/position-stmts/UP_Guidance-uniform_temp_marking_of_und_facilities.pdf

Our analysts mark each line with chalk or flags in their designated color in accordance to the APWA. We follow these guidelines nationwide anytime we perform a private utility line locate.

RedElectrical Lines, Cables, & Conduit
OrangeTelecommunication lines
YellowGas, Oil, Steam & Petroleum
GreenSewers & Drain Lines
BluePotable Water
PurpleReclaimed Water & Irrigation
PinkTemporary Survey Markings
WhiteProposed Excavation

Penhall Technologies follows these guidelines to better serve our customers. We follow through with our efforts to ensure safety 100% of the time.


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