APWA Uniform Color Codes

Red
Electric Power Lines
Cables
Conduit
Lighting Cables
Yellow
Gas and Oil
Steam
Petroleum
Gaseous Materials
Orange
Communication
Cable TV
Alarm & Signal Lines
Cables or Conduit
Blue
Potable Water
Green
Sewer and Drain Lines
Purple
Reclaimed Water
Irrigation 
Slurry
White
Proposed Excavation
Pink
Temporary Survey Markings