Call 811 Before Installing Work Zone Signs: Utility Locates for Traffic Control Crews

Most traffic control devices sit on top of the road. Cones, drums, portable sign stands and barricades touch the ground and nothing more. Then a long-term job calls for post-mounted signs, and a crew turns up with a post driver and starts putting steel into a road shoulder that carries gas, fiber and power.

That is excavation, in the sense that before-you-dig laws use the word. This guide explains how the 811 process generally works, when traffic control work triggers it, and how to build it into scheduling so it does not delay a job or hurt someone.

Before-you-dig laws are state laws. Notice periods, ticket life, exemptions and penalties differ from state to state. What follows is how the process generally works and what to ask. It is not a statement of what is required in your state. Confirm with the 811 center for the state you are working in.

What 811 is

According to the national campaign site, 811 is the free national before-you-dig service. Anyone who plans to dig should contact 811 or go to their state 811 center's website to request that the approximate location of buried utilities be marked with paint or flags.

The same site gives the basic sequence:

1. Contact 811 a few business days before digging. By phone or through the state center's website.
2. Wait for the utilities to respond. The site says you need to wait a few days and ensure that all utilities have responded before breaking ground.
3. Dig carefully around the marks.

It also makes two points that apply directly to sign installation: shallow digging is still digging, and utilities can be buried just inches below the surface.

The reason the system exists is the cost of getting it wrong. The campaign site puts damage to buried utilities at $30 billion annually. A strike can mean an outage, a repair bill sent to whoever did the digging, or a fire.

When traffic control work is digging

Ask one question about each device: does any part of it go into the ground?

Usually does not disturb the ground:

• Cones, drums, vertical panels and barricades on the surface
• Signs on portable stands with sandbags or other ballast
• Trailer-mounted arrow boards and message signs
• Water-filled or concrete barrier set on the pavement

Usually does:

• Driven sign posts for long-term or intermediate-term signing
• Posts set in drilled or dug holes with backfill or concrete
• Stakes or pins used to anchor devices or barrier
• Temporary mailbox posts where a project relocates them

State device lists show how common the second group is. TxDOT's Compliant Work Zone Traffic Control Device List, for example, has separate categories for portable sign supports and for post-type sign supports used on long-term and intermediate-term signing, and defines direct embedment as a support placed in the original soil by driving or by creating a hole and backfilling. If your job uses that kind of support, your crew is putting steel or timber into the right-of-way. Our explainer on the TxDOT compliant device list covers how that document is organized.

Road shoulders are among the most crowded places to do it. Utilities follow roads because the right-of-way is where they are permitted to be. A sign location chosen from a plan sheet for its distance from the taper may sit directly over a telecom duct.

What the safety rules say

Separate from state one-call laws, OSHA's excavation standard for construction addresses underground utilities. 29 CFR 1926.651 requires that the estimated location of underground utility installations that may reasonably be expected to be encountered be determined before opening an excavation. Whether and how that standard applies to a particular sign installation is a question for your safety adviser. The practical direction is the same either way: find out what is under the spot before you drive anything into it.

Building the lead time into the job

The most common failure is not ignoring 811. It is remembering it the afternoon before the signs go in.

A locate request needs lead time that the rest of traffic control scheduling does not. A crew can be dispatched tomorrow morning. A locate usually cannot. So the request has to be triggered when the job is planned, not when it is dispatched.

A workable routine:

• Flag it at the quote. If the scope includes post-mounted signs or anything driven, the quote should say that a utility locate is required and state the lead time you need. See exclusions and assumptions in traffic control proposals.
• Agree who makes the request. Put it in writing with the contractor. If they say their ticket covers it, ask for the ticket number and check that the described work area includes your sign locations.
• Mark the locations first where the state asks for it. Many states expect the proposed dig area to be marked in white so locators know where to look. Ask the center.
• Request it as soon as the sign locations are known. For a long advance warning series, the sign locations can be thousands of feet from the work itself. A ticket for the work area may not reach them.
• Record the ticket number, the date and the valid-through date on the job. Tickets expire. A job that slips two weeks may need a new one.
• Do not dispatch the post crew until every utility has responded. A response of "clear" is still a response you need to have.
• Brief the crew on the marks. What the colors mean in your state, how wide the caution area around a mark is, and what your state requires inside it. Ask the center for its guidance on hand digging near marks.

This is one more date-driven requirement alongside permits and notices, and it belongs in the same tracker. See multi-jurisdiction permit tracking, lane closure permits: how the process works, and our explainer on how a MUTCD traffic control permit review fits in.

In the field

If the marks conflict with the plan location, move the sign, not the mark. Then tell the contractor or engineer, because a sign moved a long way may no longer be where the plan needs it. Sign spacing has tolerances, and the person responsible for the plan should agree to the change. See field changes to an approved traffic control plan.

If there are no marks and no "clear" response, do not drive. Use a portable stand for the shift and follow up.

If the marks have been destroyed by mowing, rain or traffic, ask for them to be refreshed. Do not work from memory.

If the crew hits something, stop, keep people away, and follow your state's damage reporting rules and the utility's instructions. A gas strike is an emergency. Every crew lead should know who to call before the first post goes in.

When the job ends, pulled posts leave holes. Fill them as the permit or contract requires.

Choosing devices to avoid the problem

For a short job, the simplest answer is not to dig at all. Portable sign supports exist for exactly this. The trade-off is that portable stands need ballast, blow over, and get displaced, so they need more maintenance. See sign stands, sandbags and ballast.

For long-term signing, post-mounted signs are often required by the agency's standards and are less likely to be knocked down. In that case the locate is simply part of the installation, like the post driver.

The choice is not always yours. The plan and the agency's standard sheets usually say which support type is acceptable for which duration. Read them before you price the job.

Questions to ask the 811 center in each state

Because the rules differ, keep a short record per state. Ask:

• How many business days of notice are required, and how are they counted?
• How long is a ticket valid, and how is it renewed?
• Does driving a sign post count as excavation here? Are there any exemptions by depth or tool?
• Do we need to pre-mark the proposed locations?
• How do utilities report their response, and how do we confirm that all have responded?
• What is the required practice near a marked line?
• How do we report damage?
• Are any facilities not covered, such as privately owned lines, and how are those located?

Add the answers to the file you keep for each jurisdiction. If you work across state lines, do not carry one state's notice period into the next.

Where software helps

None of this is complicated. It fails because it depends on someone remembering a date. The fix is to make the locate a visible requirement on the job.

In practice that means a field on the job for the ticket number and its expiry, a note on the quote, and a rule that the post-installation crew is not assigned until the ticket is confirmed. Traffic OS keeps quotes, jobs, crew assignments and job files in one record, so a locate ticket can be attached to the job it belongs to and seen by dispatch and the crew lead. See the features page, or the dispatch software buyer's guide for what to ask of any system. Pricing is by flat monthly tier.

To see how job requirements and attachments appear to a crew in the field, book a walkthrough.

The short version

If it goes into the ground, treat it as digging. Contact 811 a few business days ahead, wait until every utility has responded, and install around the marks. Decide at the quote who makes the request, record the ticket on the job, and do not send the post crew until it is confirmed. The notice period and the details belong to your state's law, so ask the state center and write down what it tells you.