In March, Aii ran its original damage prevention campaign Modern Roots March to help raise America’s infrastructure IQ about the critical roots of modern life below our feet. In April, Aii joined national groups, agencies, and nonprofits to elevate National Safe Digging Month to improve excavation safety. Now as we enter the summer months, when construction and excavation damage reach their peak, we focus on practical steps to reducing damage even as we build, maintain, and update America’s infrastructure.

In this blog series, we began with the basic truth that safer digging begins before the shovel hits the ground. In particular white-lining and its innovative form of electronic white-lining (EWL) happen before digging and help both improve safety and reduce damage. This second blog in the series drills down on the safety impact of electronic white-lining and how the use of web entry for locate requests should be not only a best practice, but the preferred (if not required) form of proposed excavation notice nationwide.

Calling 811 is a great way to begin the process for safe digging. In fact, most awareness campaigns lead the public to believe it is the law to call 811. But this is only half true. While it is required by law to provide notice of a proposed excavation, and 811 is the simple nationwide call-in number, what is actually required is the notice itself, not the call to 811.

Every One-Call center in America has a website or even a smartphone application allowing homeowners and excavators to provide advanced dig notice and request a locate online. While some states and industry groups have shifted messaging to “call or click” before you dig, the overwhelming marketing emphasis remains on calling 811. This is a shame, because clicking may actually lead to safer digging and reduce damage at a greater rate than simply calling – especially where EWL is a feature in the online portal.

The Common Ground Alliance (CGA) hails the widely accepted statistic that when a call is made, damage is avoided 99 percent of the time, but in truth, this statistic is for notice provided not strictly a phone call through 811. And some good intuition and a few examples shows us that web entry of locate requests – or providing notice of proposed excavation – online rather than calling is a big part of reducing and avoiding damage.

There is a clear distinction between calling 811 and speaking to a call center agent and entering information online directly. The major distinction is that one features a middleman. That on its own does not cut either way. On the one hand, a middleman could distort information, while on the other hand, the agent may have specialized knowledge and be able to elicit better information.

In most cases, the first scenario is more likely, because the excavator themselves have more particular knowledge of the dig site than the agent fielding the call, and little specialized knowledge of the process is needed. This plays out in a game of literal telephone, with the excavator describing a dig site and lot location to a call center agent, who must then interpret it and enter it online. This can lead to error or miscommunication with things like cardinal directions, street names, “right” versus “left” orientation, scope, and scale.

By contrast, entering the information directly allows the homeowner or excavator to write detailed descriptions, describe the lot or dig site, and in many cases draw directly on a map representing an overhead view. This is known as electronic white-lining – it is a pre-marking done by the excavator that shows the precise location of the dig. This level of precision may help avoid future errors like a locator coming to the wrong end of the lot due to a poor description of where the excavation will take place.

This same thinking led Mike Sullivan, former head of the Canadian Common Ground Alliance (CCGA) and current president of Utility Safety Partners, to investigate. Sullivan said his interest in the safety implication of calling versus web entry was initially “based on a hunch… With online locate requests, the person digging plots their dig site directly onto a map; eliminating interpretation by an Agent. In my view, there had to be a benefit to that.”

This kicked off multiple rounds of internal analysis, reviewing data submitted to the Damage Information Reporting Tool (DIRT) to determine damages that occurred if a notice had been made, and if so, whether it was by phone or online.

This “deeper dive” validated the intuition. “With that data in-hand, we determined that locate requests made by phone within that dataset were twice as likely to result in damage compared to locate requests made online,” Sullivan noted. Going further, Sullivan explained that he is “fairly certain” the analysis is correct because “Similar additional analysis delivered similar results.”

While Sullivan notes that little or no widespread statistical data or public studies have been conducted beyond internal analyses, there is clear evidence in Alberta and strong intuition for why web-entered locate requests would result in safer outcomes. Much of the reason for this is due to electronic white-lining. If excavators merely enter written descriptions and addresses, there is little additional benefit to the web-entered request, and a call center agent can largely record the same information. This would then result in a locator being dispatched with an address and written description that may use relative terms like “left” and “right” or “near” this or “the area between” these.

With electronic white-lining and an aerial perspective, not only can the excavator give detailed, narrow, and precise depiction of the dig site, but the locator can see the same from an overhead view on a satellite image or map.

This has led the Canadian call centers to switch almost entirely to “Click Before You Dig” or “Click to Know” rather than “Call Before You Dig” as the messaging and requirement. There, over 75 percent of locate requests come through online rather than by phone, with their DIRT report explaining:

“In Canada, on-line / web locate requests have emerged as a preferred method of requesting a locate. Any person requesting a locate can do so 24/7/365 and is typically able to plot or draw their dig site on a sketch or map reducing the risk of misinterpretation to an Agent thereby improving the damage prevention process.”

In addition to never being on hold, eliminating telephone communication errors, and drawing a shape, Clicking before a dig can enable uploading of documents ahead of the dig that may be needed or useful to utility operators or locators. While such uploads are a feature of the Canadian system, they are also available in many U.S. One-Call centers.

Fortunately, while Sullivan is right that little statistical data is available, it does not mean no studies have been conducted on EWL. One major PHMSA-backed pilot program in Virginia details “that the application of GPS technology in electronic white-lining can be of significant benefit to the one call process.” These include “improvements in safety” with “every stakeholder benefit[ing] at least indirectly.” The reasons for safety are also intuitive: by reducing the scope of the locate, personnel can focus in on only the relevant areas, which “means less exposure time to locating crews, thus improving personnel safety,” while “smaller, more accurate areas” means “it is less likely that existing underground facilities will be affected; that is, fewer facilities will be affected within these smaller defined areas.” Pairing strong intuition with Canadian internal analysis and a high-profile pilot program in one of the leading damage prevention states makes it clear that EWL is essential for safety.

The pilot study concludes: “The bottom line is that the application of GPS-enhanced electronic white-lining technology to the one-call damage prevention process has been demonstrated through this Pilot Project to benefit the damage prevention process.” This is likely why 61 percent of excavators surveyed by CGA emphasized the safety benefits of electronic white lining. With safety always top of mind and damage prevention the literal name of the game, we agree and hope to see electronic white-lining more prominently adopted as soon as possible.

Read our intro blog here and stay tuned for the next blogs in this series explaining the environmental, economic/efficiency, and investigative benefits for electronic white-lining.


Read the full series:


Safer Digging Part 1: Before the Shovel

Safer Digging Part 2: Click Don’t Call

Safer Digging Part 3: Keep it in Park

Safer Digging Part 4: Saving Time Saving Money

Safer Digging Part 5: Investigating a Damage


Written by Benjamin Dierker, Director of Public Policy


The Alliance for Innovation and Infrastructure (Aii) is an independent, national research and educational organization. An innovative think tank, Aii explores the intersection of economics, law, and public policy in the areas of climate, damage prevention, energy, infrastructure, innovation, technology, and transportation.