Chart boundary

Does not replace a locate request, field ticket, utility marking, excavation law, or safe digging procedure.

colour legend

Colour-to-utility field legend

Use the colour legend to recognize markings, then follow the locate ticket and local safe digging process.

Scopejobsite safety and clearanceX-axismarking colourY-axisfield actionReviewAnnualNextUnderground wiring to a detached garage or shed
Colour-to-utility field legendmarking colourRedElectric powerOrangeCommunicationYellowGas / oilBlueWaterGreenSewer / drainagePurpleReclaimed water /...PinkTemporary surveyWhiteProposed excavationfield action
Use the colour legend to recognize markings, then follow the locate ticket and local safe digging process.
RedElectric power

Power lines, conduit, lighting cables.

OrangeCommunication

Telecom, fibre, cable TV, signal.

YellowGas / oil

Gas, oil, steam, petroleum.

BlueWater

Potable water and irrigation.

GreenSewer / drainage

Sewer and storm drainage.

PurpleReclaimed water / irrigation

Reclaimed water, irrigation, and slurry where used locally.

PinkTemporary survey

Survey markings or temporary investigation marks.

WhiteProposed excavation

Work area pre-marking.

Decision reference

Show the field meaning of common locate colours before excavation planning.

Reference basis: Utility Safety Partners colour code and Canadian one-call locate guidance.
ColourTypical meaningField useBoundary
RedElectric powerPower lines, cables, conduit, lighting cablesConfirm ticket and marks
OrangeCommunicationFibre, telecom, signal, alarm, cable TVConfirm owner and marks
YellowGas or oilGas, oil, steam, petroleum facilitiesFollow excavation rules
Blue / GreenWater / sewerPotable water, irrigation, sewer, drainageConfirm local code
WhiteProposed excavationWork area pre-markingNot a locate clearance

Use notes

  • Use this chart as a planning and conversation aid only.
  • Confirm current utility requirements, product markings, manufacturer instructions, and local authority requirements before field work.
  • Use the linked calculator or table when the task needs project-specific arithmetic.

Reference sources

Open the underlying public references before treating the chart as project guidance.