“Do I have to call before I set fence posts?” As a rule, yes. Federal law says a person doing demolition, excavation, tunneling or construction may not dig in a state that has adopted a one-call notification system “without first using that system to establish the location of underground facilities” (49 U.S.C. §60114(d)). The Common Ground Alliance’s Best Practices note that all 50 states have one-call legislation and/or established 811 centers. Under definitions like California’s (below), a post hole dug with an auger is excavation; so is a trench for a French drain or a hole for a footing.
The trades whose digging most often hits lines with no ticket are the ones reading this. The Common Ground Alliance’s 2024 DIRT report analyzed 196,977 damage reports; failure to notify 811 was the top root cause of damage to buried utilities, at 24.54%, and fencing and landscaping work led that “no locate request” category at 28%, ahead of construction and development at 24%. CGA’s summary of 2025 data, published in July 2026, counted 221,717 damage reports and found failure to notify was again the single largest root cause.
Here is how the process works, with California and Florida as worked examples of what a state law says. Your state’s rules will differ in the details, so look yours up on the state 811 center directory.
What counts as digging
State laws define excavation broadly. California’s reads “any operation in which earth, rock, or other material in the ground is moved, removed, or otherwise displaced by means of tools, equipment, or explosives,” and lists grading, trenching, digging, ditching, drilling and augering among the ways (Gov. Code §4216(g)). Florida’s covers any manmade cut, cavity, trench or depression “intended to penetrate or disturb the surface of the earth” (Fla. Stat. §556.102(6)).
Exemptions exist, but read them closely before you lean on one. Florida’s exemption for homeowners covers excavation by the owner of a single-family property on their own land, or for that owner by a utility or its agent, “only up to a depth of 10 inches” (§556.108(1)). It is written for the homeowner and the utility, not for a fence or landscape company the homeowner hired. The national 811 site is plain about it: contact 811 before any digging, “including common projects like planting trees and shrubs or installing fences and mailboxes.”
The ticket, step by step
- Mark the dig area in white. CGA Best Practice 5.2 calls for white paint, flags or stakes on site, electronic white lining where the 811 center offers it, or a clear description on the ticket. California makes it a duty: an excavator “shall delineate the area to be excavated” before notifying the center, and an operator may decline to mark until it is done (§4216.2(a)). For a fence, paint or flag the line and each corner and gate post.
- Make the request early enough. CGA’s recommended practice, unless state law says otherwise, is a start date at least two working days and not more than fourteen full working days after the request (Best Practice 5.1). California: at least two working days and not more than 14 calendar days before you dig, and the day you call does not count (§4216.2(b)). Florida: not less than 2 full business days (§556.105(1)(a)). North Carolina 811 asks for three working days. Florida lists what the ticket needs, among it the address and nearest intersection, the start date and duration, whether machinery will be used, the type of work, the approximate depth and who the work is for.
- Wait for every response, not just the paint. California says not to begin until every operator listed on the ticket has fulfilled its obligations (§4216.2(g)); Florida says to verify the system’s positive responses before you start (§556.105(9)(c)). The 811 site says that on average 7 to 8 utility operators are notified for each request. Late responses are common: in data from eight 811 centers, CGA found excavators were unable to start on time an average of 38% of the time on standard tickets. Do not book the crew for the legal start date with nothing else to do.
- Keep the ticket alive. A California ticket is valid for 28 days and must be renewed by the end of the 28th day if work continues (§4216.2(e)); Florida’s is valid for 30 calendar days (§556.105(1)(c)). If the marks are gone before you are done, Florida says stop digging near the facility and ask for a re-mark (§556.105(11)).
The locate itself costs you nothing. CGA Best Practice 5.31 says locations are provided by operators “at no cost to excavators,” and the 811 site calls itself “the free national before-you-dig service.”
Digging near the marks: the tolerance zone
A mark shows the approximate location of a line, not its exact spot, so state laws draw a zone around it where machines stay out. The 811 site says state laws generally prohibit mechanized equipment within 18 to 24 inches on all sides of a marked utility, and calls that the tolerance zone. CGA’s Best Practice 5.19 uses the width of the facility plus 18 inches on either side. California uses 24 inches on each side of the field marking (§4216(u)); Florida, 24 inches from the outer edge of either side of the marked facility (§556.102(15)).
Inside the zone, you find the line by hand before any power equipment goes in. California requires hand tools to determine the exact location “before using any power-driven excavation or boring equipment within the tolerance zone” (§4216.4(a)), with vacuum excavation allowed if you said so on the ticket and the operator agreed. Florida names hand digging, pot holing, soft digging and vacuum excavation (§556.105(5)(c)).
Say a fencer’s line runs parallel to a marked gas service, and two of the posts land inside the tolerance zone. The choices are to move those posts, change the spacing, or hand-dig those two holes until the line is exposed and the auger can clear it. What is not on the list is running the auger and hoping.
The lines 811 will not mark
The utilities mark their own lines, and the lines the property owner owns may not be marked at all. North Carolina 811, for example, says: “Secondary water, sewer, gas and electric are considered private lines and will not be marked when contacting 811,” water, sewer and storm drain lines are marked only within the right of way or to the meter, and you will need to pay a private line locator for the rest. Check your own state center’s page for where its line falls.
So ask the owner before you quote: is there irrigation, landscape lighting, a line out to a shed or a detached garage, a pool, a septic system? If the answer is yes or “I don’t know,” a private locate goes on the estimate as its own line, or the risk goes in the contract in plain words.
If you hit something
Who pays when a line is hit
Following the steps is what protects you. In California, an excavator who damages a line after failing to follow the notice and tolerance-zone rules is liable to the operator for the resulting damages, costs and expenses that failure caused; an excavator who followed the rules is not liable for damage caused by an inaccurate mark (§4216.7(a) and (d)). On top of that sit civil penalties of up to $10,000 for a negligent violation and up to $50,000 for a knowing and willful one, and the Registrar of Contractors at the Contractors State License Board enforces the law against contractors (§4216.6).
In Florida, if you did not give notice and then damage a line, “it is rebuttably presumed that the person was negligent,” and if found liable you pay the total losses of all the utilities involved, with lost revenue and loss of use capped at $500,000 per facility (§556.106(2)(a)). Skipping the notice is also a noncriminal infraction that can cost a $500 civil penalty plus court costs, or $2,500 where the line carries hazardous materials regulated by the federal pipeline safety agency (§556.107).
A routine that makes it automatic
- Every job with digging gets a ticket number on its work order before it gets a start date. In Florida, the ticket number must be shown to a law enforcement officer or code inspector who asks (§556.105(4)).
- White-line the dig area when you measure, so the request goes in the same day.
- Schedule the dig day after the legal start date, with a fallback job for the crew.
- Check every positive response on the ticket the morning of the dig, and photograph the marks.
- Ask about private lines at the estimate and price the private locate when needed.
- Renew the ticket before it expires on a long job, and call for a re-mark when the paint fades.
Fencing and landscaping lead the no-locate-request numbers, and the locate costs nothing. If you run a fence company, a landscaping crew or an excavation outfit, make the ticket part of every job the way the estimate is.
General information, not legal or tax advice. Rules change and vary by state; check with the agency named above or a professional for your situation.