Tips for the Non-Surveyor

Have you ever been curious about surveying markouts and/or what the flags and spray paint mean?

These color codes follow a guideline suggested by the American Public Works Association (APWA). Utility markouts have 6 main colors, and can be referred to as color systems, survey flag colors, survey color codes, and other similar names. Even though there are multiple names for utility markouts, the meanings behind the color codes and what they are used for always remain the same.

The 6 main survey color codes are as follows:

  • Red is used for electric power lines;
  • Orange is used for telecommunications;
  • Green is used for sewers and drain lines;
  • Yellow is used for natural gas, oil, steam, and petroleum;
  • Purple is used for unknown utilities; and
  • Blue is used for potable water.
Image from Utility Survey US