How to Mark Underground Utilities Before Digging
Request utility locates before every post hole, wait for responses, and remember private lines may not be marked.
By Fence Planner · 1 min read · Updated 2026-07-21
The short answer
Do not dig from a planner diagram alone. Request the locate service that covers your area, wait for every response, and follow that authority’s instructions. Public marks are not a complete picture of private lines on your property.
Public locate vs private lines
A public locate notifies member utilities so they can mark their facilities. Irrigation, landscape lighting, private water lines, and other owner-installed services are often outside that ticket. Walk the dig line for private risks separately — this guide does not invent a universal tolerance distance.
Do this first
- Contact the locate service that covers your dig site (US: 811 / call811.com; Canada: your provincial one-call via Click Before You Dig).
- Provide the dig location and timing accurately.
- Wait for every utility response and read the paperwork.
- Walk the marks on site and treat each one as a safety boundary.
- Check for private-line risks the ticket may not cover.
- Move any conflicting post, gate, or bay before you dig.
Build Readiness Audit
Mark locate status and private-line checks on the printable field kit before you buy concrete or dig.
Open the Build Readiness AuditPrintable field kit — answers stay in your browser.
Use Fence Planner for this part
Adjust the proposed layout when a confirmed utility or required clearance affects a post location. Never assume a small on-screen shift makes digging safe.
Official locate portals
- Call 811 — Know what’s below — Common Ground Alliance / 811Checked 2026-07-21US entry point for calling or clicking before you dig; local one-call centers vary by state.
- Click Before You Dig — Canadian one-window locate portalChecked 2026-07-21Canada does not use a single national 811 number everywhere — use the provincial/territorial service linked from this portal.
Educational planning content only. Not a substitute for local codes, surveys, engineering, or professional advice. See Methodology for how this guide was prepared and how the calculator works.