Call 811 Before You Dig: Utility Marking and Site Access for Bay Area Excavation

Most excavation delays have nothing to do with the machine. They come from a utility ticket nobody opened, a side gate two inches too narrow, or a sprinkler line no one knew was buried there. Three things decide whether a dig day runs smoothly: the 811 notification, the access path, and the prep done before the crew arrives. This guide covers all three for homeowners planning grading, trenching, foundation digging or site prep in the Bay Area.

Who calls 811 — and who actually does

California’s underground-safety law (Government Code §4216 and following) defines an “excavator” broadly: a contractor, a property owner, a utility. It defines “excavation” just as broadly: grading, trenching, digging, ditching, drilling, augering, scraping and similar work all count, and the definition sets no minimum depth.

When you hire a contractor to dig, the contractor is the excavator, so opening the ticket is their job. Quartz builds the 811 ticket into the schedule on excavation projects, and you should ask any contractor for the ticket number and legal start date before a machine is booked. If you are digging yourself, do not hunt for exemptions. USA North 811’s guidance is the same for everyone: submit a ticket at least two working days ahead. It costs nothing.

The two-working-day clock, step by step

The process looks like paperwork, but each step has a physical meaning on your property.

1. Before day 0Mark the dig area in whitePaint, flags or stakes outline the planned excavation. The statute calls this “delineating.” Keep markings tidy and check local rules.
2. Day 0Open the ticketSubmit online or dial 811. You receive a ticket listing the utilities notified and a legal excavation start date and time.
3. Days 1–2Utilities respondEach utility with lines nearby marks them or reports that it has none. Confirm every utility on the ticket has responded.
4. Start dateDig with careWork starts on the ticket’s date, or any later date up to 14 calendar days out. The ticket is valid for 28 days and must be renewed if work runs longer.

Use the date and time printed on your ticket rather than counting days yourself. The law counts a working day as a weekday, Monday through Friday, 7 a.m. to 5 p.m., excluding federal and state holidays. That is why a Friday-afternoon call and a Monday-morning call can produce very different start dates.

The 24-inch rule: where the machine stops

Each utility mark shows the horizontal path of a line. It does not show depth. California defines a “tolerance zone” as 24 inches on each side of the mark. Inside that strip, the line’s exact position must be confirmed with hand tools before power equipment is used there (the law also allows vacuum excavation in some cases). It also says to presume every line is active.

Reading the paint: what the colors mean, and what is never marked

Utility marks follow the American Public Works Association color code, which California’s statute references. You will see these on lawns, sidewalks and driveways after the locators visit:

• White — proposed excavation
• Pink — temporary survey marks
• Red — electric
• Yellow — gas, oil, steam
• Orange — communications
• Blue — drinking water
• Purple — reclaimed water
• Green — sewer and storm drain

Now the part that surprises homeowners. Utilities only mark lines they own. USA North 811 states that private lines will not be marked, including landscape irrigation and lighting, a gas line to a barbecue, and electrical service to a detached garage or shed. Those are exactly the lines a backyard excavation tends to find. Tell your contractor what you know about them, and ask how they plan to locate the rest, whether from original plans, a private locator, or careful hand digging.

One more practical point from USA North: if the marks fade or get disturbed during the job, work in that area stops, and re-marking is requested on your existing ticket.

Will a Bobcat fit? Measuring your access

Compact loaders go places full-size equipment cannot, but side yards, tight gates and low roofs still decide what is possible. The photos below come from a Quartz project and show how little room there can be: a wooden fence on one side, a temporary canopy frame overhead, and a path barely wider than the machine.

Before you ask for a quote, measure these and send photos:

• The narrowest point on the path from street to work area: a gate, the gap between a fence and an AC pad, a meter, a downspout, a hose bib.
• Overhead clearance: eaves, pergola beams, tree limbs and wires. A raised bucket and the cab stand much taller than the machine’s width suggests.
• Surface and slope: steps, soft soil, wet clay or a steep grade can rule out a route that looks fine on a dry day.
• Staging space: somewhere for the soil pile, the debris, and a truck or dumpster close enough to load. Check whether your city requires a permit to put a bin or truck in the street.

If a machine will not fit, part of the job becomes hand work, which is slower and costs more. Our guide on Bobcat excavation versus hand digging shows where that line usually falls.

Depth matters as much as access: once a trench reaches 4 feet, Cal/OSHA requires a safe exit within 25 feet of travel, and at 5 feet a protective system and a permit come into play. Our trench safety guide walks through both thresholds.

Dig-day checklist

Run through this a few days ahead. It works as a plain list without JavaScript; with it on, you get a progress bar and your ticks are remembered in this browser only.

What dig day looks like

A well-prepared excavation follows the same rhythm whatever the project:

1. Walk-through. The crew compares marks, ticket and the plan, and agrees on the route and the staging spot.
2. Hand exposure near marks. Where the work crosses or approaches a line, the crew exposes it by hand within the tolerance zone before any machine works there.
3. Machine work in passes. Soil is moved, graded or dug in controlled passes, with the operator watching for anything the marks did not predict.
4. Haul-off and cleanup. Spoil and debris leave the site and access paths are restored.

When something unexpected turns up

An unmarked line is not a reason to push on. Pausing to identify it costs a day. Striking it can cost far more, in repairs, outages and safety.

Questions homeowners ask

Related services and guides

• ServiceBobcat excavation: foundation digging, trenches and site prep
• ServiceBobcat grading and leveling
• ServiceBackyard grading and drainage correction
• GuideBobcat services explained: what they are and when you need one
• GuideBobcat excavation versus hand digging
• GuideThe complete guide to Bobcat grading for Bay Area yards