Post Hole Digging without first checking for underground utility lines is a dangerous and potentially life-threatening practice. Let us help you understand the utility marker colour codes that indicate where you can and cannot dig with this guide to Call Before You Dig!
When you call Ontario One to have your utilities marked before you dig, the contractors will come out and spray-paint or place flags at the locations of your buried utilities. The colours of these markings indicate what type of utility is buried there.
When digging post holes in Oakville, Burlington and Hamilton there are eight standard colours for utility markings, as follows:
Red: Electric power lines, cables, conduits and lighting cables
Yellow: Gas, oil, steam, petroleum or other flammable materials
Orange: Communication, alarm or signal lines, cables or conduits
Blue: Potable water
Green: Sewers and drain lines
Purple: Reclaimed water, irrigation and slurry lines
Pink: Temporary survey markings
White: Proposed excavation
If you see any markings that are not one of these eight colours, assume that it is a private utility line that has not been properly marked. Do not dig until you have contacted the owner of the line to have it properly marked.
