Construction utility flags are small colored markers that show where buried lines run before anyone digs. Red means electric, yellow means gas, orange means communications like fiber, blue means drinking water, green means sewer, purple means reclaimed water, pink means survey marks, and white means proposed digging.
Greenlight Networks has been building fiber since 2011 and now serves more than 320,000 homes and businesses. That means our neighbors see these flags in their yards often, and we want you to know exactly what they are telling you.
What do the different utility flag colors mean?
Every color maps to one type of buried utility. The colors come from the American Public Works Association (APWA) Uniform Color Code, which crews across the country use so that everyone reads the same signals.
Flag color
|
What it marks
|
White
|
Proposed excavation (where digging will happen)
|
Pink
|
Temporary survey markings
|
Red
|
Electric power lines, cables and conduit
|
Yellow
|
Gas, oil, steam, petroleum or other gaseous materials
|
Orange
|
Communication, alarm or signal lines, including fiber and cable
|
Blue
|
Drinking water
|
Green
|
Sewer and drain lines
|
Purple
|
Reclaimed water, irrigation and slurry lines
|
The APWA developed this system to reduce damage to workers, the public, and vital services. The same colors are used on flags, spray paint and stakes, so a painted line on your sidewalk follows the same rules as a flag in your lawn.
Why are there colored flags in my yard?
Colored flags mean someone requested a locate, and utility owners sent crews to mark their buried lines. The request may not have come from you. A neighbor, a utility, a city or a contractor working nearby may have called 811, and markings can extend across property lines.
Flags do not mean your property will be dug up or that anything is wrong. They are a safety step that happens before work begins. Marking with flags, paint, or stakes lets every excavator see the type and approximate route of buried lines.
What does an orange utility flag mean?
Orange marks communication lines. That includes telephone, cable TV, alarm and signal lines, and the fiber-optic cable that carries internet service. If you see orange flags in your neighborhood, a communications provider is either planning work or protecting existing lines.
Orange flags do not tell you which company owns the line. Look for letters or initials painted beside the flags, which usually identify the utility that placed the marks. If you are unsure, your local one-call center can help you sort out who marked what.
What do red and yellow utility flags mean?
Red flags mark electric lines, and yellow flags mark gas, oil and steam lines. These two colors carry the highest safety stakes. Striking an electric or gas line can cause serious injury, fire or explosion, along with outages for you and your neighbors.
That is why the rule is simple: never dig near red or yellow flags without a current locate ticket, and dig by hand near any marked line. If you smell gas or see damage to a line, leave the area and call 911 and your gas utility from a safe distance.
What do blue, green and purple utility flags mean?
Blue flags mark drinking water lines, green flags mark sewer and drain lines, and purple flags mark reclaimed water, irrigation or slurry lines. A green flag does not mean “go.” It means a sewer or drain line is buried below.
These colors cover the pipes that keep your home running. A break in a water main can flood a street, and a damaged sewer line can release contaminants, so crews treat these marks with the same care as electric and gas.
What do white and pink utility flags mean?
White marks where new digging is planned, and pink marks temporary survey points. White is the odd one out because it is not a utility. It outlines the dig area, and many locate programs require it when the dig site cannot be described clearly in the locate request.
Pink flags come from surveyors and engineers who are measuring the site before design or construction. You may see pink flags months before any digging starts.
Are private utility lines marked with flags?
No. Public locate services mark the utility owner’s lines, not the private lines on your property. A sewer lateral from your house to the main, a septic system, a private gas line to a grill or a buried sprinkler line usually will not appear on a free 811 locate.
Hunker’s guide to green flags notes that private drainage lines require a private locator, who uses the same color code. If you plan to dig near a shed, pool, detached garage or irrigation system, hire a private locator in addition to calling 811.
How long do utility flags stay in the ground?
Utility markings stay valid for a limited window, and the length varies by state. Many programs treat marks as valid for about 10 working days, as long as work begins on time and isn’t paused for long. Check your local one-call center for the exact rule where you live.
If flags fade, wash away or get moved, the marks may no longer be reliable. Crews should request a re-mark before continuing. The Common Ground Alliance publishes damage prevention information for every state.
What should I do when I see flags on my property?
Leave them in place, and do not mow over, pull up, or rearrange them. Flags and paint are temporary and will not harm your lawn. Moving them can put a crew at risk and can force the project to stop and restart.
Here is a simple checklist:
Leave the flags where they are. Crews rely on exact positions.
Keep pets and children away from stakes and wire. Flags are thin and easy to trip over.
Watch for crew notices. Contractors often leave door hangers or send updates about upcoming work
How does Greenlight Networks use utility flags during fiber construction?
Before our crews dig or bore, we use the one-call system to mark existing utilities. That step protects your electric, gas, and water service, and it protects our crews. Our construction process has five stages, and marking happens during the build stage.
The full timeline matters because flags are one of the last visible steps. Getting to the build stage involves:
Utility pole approvals: The pole application process can take up to 365 days.
Construction: Building a district takes anywhere from 60 days to 6 months, depending on whether the work is aerial or underground.
Installation: Once your neighborhood is built and you order service, in-home installation generally takes 2 to 4 weeks.
Our 5 Steps to Fiber guide walks through each stage. If you see flags in your neighborhood and want to know whether fiber is coming, check your address on our availability page to get construction updates by email.
Frequently Asked Questions About Utility Flags
Does a utility flag in my yard mean my internet is changing?
Not necessarily. Flags mark any buried utility, and any nearby digging project can trigger them. Orange flags point to communications lines, but they do not tell you which provider is building. Check for a door hanger or notice, or look up your address to see whether Greenlight construction is planned.
Can I pull up flags after the work is done?
Once construction in your area is finished, the flags are no longer needed and can be removed. Do not remove them while work is ongoing, because crews may still be relying on them. If you are unsure, ask the contractor or company named on the notice.
What is the difference between flags and paint?
They carry the same meaning. Crews use flags on grass and soft ground, and spray paint on pavement and hard surfaces. Both follow the same APWA colors, and both may include letters and numbers that identify the utility owner or the line’s size and direction.
Ready for fiber that is built with care? Check availability at your address and get construction updates for your neighborhood.
Want to see what happens after the flags go in? Read our 5 Steps to Fiber guide for the full timeline.
