What are the American Publick Works Association (APWA) Uniform Color Codes?

The American Public Works Association (APWA) has established a standardized system of color codes for the temporary marking of underground utilities throughout the United States. This system ensures consistent and clear communication to prevent damage during excavation activities. Here’s a detailed breakdown of these color codes:


  • Red: Designated for marking electric power lines, cables, conduit, and lighting cables.
  • Orange: Used to identify telecommunication lines, including alarm or signal lines, as well as cables or conduit.
  • Yellow: Indicates the presence of natural gas, oil, steam, petroleum, or other gaseous and flammable materials.
  • Green: Represents sewer and drain lines.
  • Blue: Marks drinking water sources to alert operators of safe water supply lines.
  • Purple: Signals reclaimed water lines, including irrigation and slurry systems.
  • Pink: Used for temporary survey markings or to mark unknown or unidentified facilities.
  • White: Outlines the proposed excavation limits or routes, guiding the planned work area.

These color codes provide essential guidelines for construction and maintenance work, ensuring the safety and efficiency of operations where underground utilities are concerned.

 

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