What are those color markings outside at my property?

All persons planning an excavation in the state of California are required to notify Underground Service Alert (USA) of their intend at least two (2) working days prior to beginning excavation (California Government Code 4216). When someone notifies USA that there is an excavation planned, USA notifies all of the utilities that have underground facilities in the designated area to mark the approximate location of their facilities.


Utilities are required to mark their facilities in a color code as follows:

• White = proposed excavation area
• Red = electric
• Orange = communications (telephone or cable)
• Purple = reclaimed water, irrigation and slurry lines
• Pink = temporary survey markings
• Yellow = gas, oil, steam, petroleum, or gaseous materials
• Blue = potable water
• Green = sewer and drain lines.

Underground Service Alert provides a protection for both the public and the persons working underground from potential explosions, electrical shocks and inconvenient outages of service.