Underground Utility Marking Colors

How to Read Utility Markings

Embarking upon any project which requires digging or the potential of encountering buried utility connections carries risk. To mitigate this risk, individuals will often request that power, gas, water and phone lines be marked with fluorescent paint. It is important for service professionals and homeowners to learn how to read utility markings.

The American Public Works Association has established guidelines for which colors should be used in utility marking. The association of specific colors with specific utilities is beneficial in that it helps workers to immediately identify which utilities they may encounter. To read the paint markings, one only needs to memorize a small set of color associations which are presented in the table below:

Utility Color Code Chart

Paint Color Use
Red is used to mark electric power lines, cables, conduits and lighting cables
Orange is used to designate telecommunication, alarm or signal lines, cables or conduit
Yellow is used to mark natural gas lines, oil, steam, petroleum, or other gaseous or flammable material
Green designates sewers and drain lines
Blue is used to mark drinking water lines
Purple is used for reclaimed water, irrigation, and slurry lines markings
Pink is used for temporary survey markings and to designate unknown/unidentified facilities
White is used to delineate proposed excavation limits or route

When a specific color of paint is observed in the working area, individuals should regard this area as a potential hazard for encountering buried utilities.

Utility paint codes were created through a joint effort between the APWA and service workers to standardize the use of marking paint from area to area. These codes are accepted in all areas of the country. While familiarizing oneself with this table of codes takes only a few minutes, the benefits of doing so are ongoing and reduce risk to anyone working around buried utility lines.