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Understand Locator Marks

  • Utility locator markings protect you.
    Make sure you and your crew know how to read utility locator markings and know the American Public Works Association uniform color code for marking underground utilities. Color code charts usually are available from your local one-call utility notification service.
  • Locator flags are placed within paint marks.
    If you find flags outside the borders of locator markings, someone may have tampered with them. Contact your local one-call utility notification service.
APWA Color Codes:
Electric Power Lines
Gas, Oil or Steam
Communication Lines, Cables or Conduit
Potable Water
Reclaimed Water, Irrigation and Slurry Lines
Sewers and Drain Lines
Temporary Survey Markings
Proposed Excavation

In Iowa, call 800-292-8989; in Illinois, 800-892-0123; in South Dakota, 800-781-7474; in Nebraska, 800-331-5666. Offices are open 24 hours a day, 365 days a year.