American Public Works Association color code for locator marks

Underground utility lines are marked with flags and/or paint in accordance with the color code below.

Red Electric power lines
Pink Temporary survey markings
White Proposed excavation
Yellow Gas, oil or steam
Blue Potable water
Green Sewers and drain lines
Orange Communications lines, cables or conduit
Purple Reclaimed water, irrigation and slurry lines

Facility markings show you only the approximate location of buried utility lines. Before you can safely work near a gas or electric line, you must first hand dig to expose the line and visually verify its exact location and depth. If you cannot visually verify the location of a marked utility line, STOP digging and call 811 immediately.

Locator marks
National Grid flag marker