What is the APWA Uniform Color Code?

The American Public Works Administration (APWA®) is a non-profit organization of companies, public works agencies, and individuals, and is headquartered in Kansas City, MO. APWA® also has a field office located in Washington, D.C.

The APWA® Uniform Color Code is a marking guideline that is universal and should be used by all professional underground utility locating companies. It provides universal understanding of the marking of underground utilities for both construction and engineering projects. It helps to prevent accidents and damage to subsurface utilities by contractors, excavators, and anyone else digging around underground utilities.

Having a uniform color code, companies and individuals always know what to expect when working around a colored line, because the color has meaning.

• Red is used to denote high and low voltage electric.
• Yellow is used to designate natural gas, steam, propane, and other fuel or heating products such as fuel oil.
• Orange is used to illustrate Telephone, Fiber Optics, Cable TV, Satellite, and other types of Communications lines.
• Blue is used to mark out potable (drinkable) water sources such as City, Municipal, and Domestic Water.
• Green is used to designate storm and sanitary sewer pipes, both gravity and forced.
• Purple is used to signify non-potable (non-drinkable) water sources such as grey water, pond water, irrigation, and slurry lines.
• Pink is generally used by surveyors for temporary survey markings. Utility Locator, LLC uses pink to designate Unknown Utilities.
• White should be used by the excavation company performing work to mark out the area that needs to be surveyed.