Digging fence post holes counts as excavation. In Texas you or your contractor must contact 811 first.
The rule
Texas811 says Texas law requires you, or your contractor, to contact 811 two business days (excluding weekends and holidays) before you dig, even in your own backyard. "Building or repairing a fence" is one of the projects it lists. The service is free.
If you hire a contractor
Texas811 says it's the contractor's responsibility to make the 811 notification. You can ask for the ticket or notification number before work starts.
What usually isn't marked
Utilities mark their own lines. Privately owned lines, such as sprinkler lines, a line to a detached shop or a private water line, are usually yours to locate. A plumber, electrician or private locator can help.
The law
The underlying law is Texas Utilities Code chapter 251 (Underground Facility Damage Prevention and Safety).
General information only, not legal or engineering advice. Rules change, so confirm with the agency linked below or a licensed professional before you start work.
Sources
Last reviewed: October 2026.
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