Understanding Utility Flag Colors: A Guide to Ground Marking

If you’ve ever seen small, brightly colored flags sticking out of the ground and wondered what they mean, you’re not alone. These flags are used to mark underground utilities and are color-coded to indicate what lies beneath. Here’s a guide to understanding what each color represents.

Understanding Utility Flag Colors: A Guide to Ground Marking

The American Public Works Association (APWA) Uniform Color Code

In the United States, the American Public Works Association (APWA) has established a uniform color code for marking underground utilities. This helps prevent accidents and damage during excavation work.

The Meaning of Each Color

  • Red: Electric power lines, cables, conduit, and lighting cables.
  • Yellow: Gas, oil, steam, petroleum, or other gaseous or flammable material.
  • Orange: Communication, alarm or signal lines, cables, or conduit.
  • Blue: Potable water.
  • Purple: Reclaimed water, irrigation, and slurry lines.
  • Green: Sewers and drain lines.
  • White: Proposed excavation limits or route.
  • Pink: Temporary survey markings, unknown/unidentified facilities.

Understanding the color coding of utility flags is crucial for safety, especially before starting any digging or excavation project. Always remember to call your local utility locator service before you dig to ensure all utilities are properly marked and to prevent any potential damage or danger.

As an Amazon Associate we earn from qualifying purchases through some links in our articles.