Looking ahead to the year 2030, we hope to see technology integrated into virtually every activity we do. For damage prevention, this is not merely aspirational, it is a necessity. Fortunately, industry groups have already cast this vision, stating in the latest Common Ground Alliance (CGA) Technology Report that the ideal dig of the future will feature a host of technology at every stage.

But without taking concrete steps today, 2030 will come and go, and damage prevention efforts will be no more technologically advanced than they were 10 years ago when much of the cutting-edge technology and best practices available today (but still not adopted systemically) were just being created.

We have explained before why It is Time for Nationwide Adoption of Enhanced Positive Response. But there is another, more foundational technology that is essential for the damage prevention process: Electronic White-Lining (EWL).

There is a reason CGA’s dig of the future begins with EWL – it is the very first step of a responsible, efficient, and safe dig done alongside providing notice of intent to dig. This is why CGA’s 16 diverse member stakeholder groups all agree that white-lining (or pre-marking) is a best practice and why CGA working groups have homed in on virtual white-lining as the most effective and efficient method of pre-marking. These industry stakeholders are joined by safety regulators and other groups, which also extol the benefits of effective pre-marking, electronic data sharing, and EWL, including the Pipeline and Hazardous Materials Safety Administration (PHMSA), the National Transportation Safety Board (NTSB), state governments, and dredging associations among many others. Yet in spite of these endorsements and interest, little action has been taken to establish this technique as a baseline practice nationwide.

Our recent blog series explained five reasons that EWL is important, including providing clarity, reducing damage, mitigating environmental disruption, saving both time and money, and preserving a digital record of the dig site for investigations if a damage does occur. These not only explain why it is useful or valuable on any individual dig, but why it is a needed threshold technology and practice across the country for every dig.

The United States is plagued with nearly $100 billion in waste and inefficiency from excavation damage every year. Excavation damage trends are also on the rise, meaning this economic cost is likely to rise as well. Setting this against record inflation and economic uncertainty, there is not a penny to waste, and safer more efficient construction is essential to maintaining modern life and rebuilding our critical infrastructure. EWL, alongside other technology like enhanced positive response (EPR) can guarantee these outcomes, save money, and keep construction jobs on schedule.

The primary source of economic harm and loss on construction jobs is digging or excavation that hits pipelines and other buried utilities because the ground is opaque and over 20 million miles of subsurface infrastructure lines are buried nationwide. To avoid this, construction companies and excavators notify state One-Call centers that they intend to dig in an area, which allows the call center to notify all the utility operators with infrastructure near the dig site. EWL is the best way to provide that notice of intent to dig.


Electronic white-lining offers excavators the chance to draw a picture or map of their dig site directly on an overhead image from satellite or fly-over photography. Whether integrated through GoogleMaps or another software system, excavators can draw a polygon of their dig directly rather than write text descriptions about site dimensions, cardinal directions, or relation to landmarks. EWL not only enables precise pre-marking, but it does so virtually so that the excavator, One-Call center, all implicated utilities, and locators can all see the proposed dig site from their respective bases of operation. This shared platform gives all stakeholders access to the precise dig site information immediately and avoids meetings on site, multiple site visits to physically white-line (or pre-mark), and offers utilities the chance to determine from afar if their infrastructure is even near the dig site (given that One-Call centers add substantial buffer to proposed excavation sites).

EWL is also necessary for certain types of excavation where pre-marking on site is either prohibitive or impossible, such as waterways or certain disaster responses. Utilizing virtual platforms for both pre-marking and utility marking can help dredging projects avoid striking pipelines and aid in recovery from storms, natural disasters, or forest fires. This may be particularly important for projects conducted and overseen by the Army Corps of Engineers.

Safety and Damage Avoidance

Evidence from Virginia’s PHMSA-backed pilot program on EWL and from internal analysis by the Canadian Common Ground Alliance (CCGA) demonstrates that allowing excavators to draw maps directly when providing notice can lead to reduction in damage during an excavation project. The internal study conducted by leaders at CCGA found that even measured against notice provided by phone (e.g. calling 811) web-entry tickets can be twice as likely to avoid damage. While not all web entry qualifies as electronic or virtual white-lining, the map integration to provide notice is a substantial benefit to safety. Where EWL goes a step further is by ensuring that the same map drawn is also provided to the utilities and locators, rather than what commonly occurs: an excavator’s self-drawn polygon is translated into a One-Call center polygon, which is then either given to utilities/locators as a general area or passed along in visual form as a large buffered circle.


The use of precision mapping helps narrow the scope and scale of the job site, which limits how many vehicles go to the site and how long they are there. First, EWL replaces the need in many circumstances for excavators to visit the site to physically pre-mark. Second, it can provide better ticket screening or simply reduce the size of the buffered dig site so that utilities far from the actual dig site do not visit or send locators unnecessarily. Finally, locators who must visit the site can avoid marking large areas when the true dig site is narrower in scope. This spares vehicle trips, idling, and time, and in the course of it, reduce environmental harm and direct vehicle emissions. Beyond this, by improving the precision and enhancing the communication between excavator and locator, there is a reduced risk of damage during the excavation, preventing damage outcomes like methane leaks or hazardous liquid spills. When these are avoided, it also avoids the added vehicle emissions from emergency response vehicles, investigators, and project delays.


Use of EWL is explained by the Common Ground Alliance as one of the “greatest return on investment” in the industry. Pilot programs in Virginia concluded that “nationwide, the potential savings in locate costs alone could exceed $120 million.” That was using moderate assumptions back in 2007, well before the nearly 10-year nationwide rise in excavation damages. These cost savings and return on investment come from making the job more efficient – sparing time and resources as detailed above. Another place that can spare resources is the One-Call center. In Canada, the Alberta one-call center was able to reduce its personnel by over 40 percent while simultaneously expanding its scope of operation to cover Saskatchewan and Manitoba as well. This was by shifting primarily to 98 percent web-entry tickets and reducing call-in locate requests. That is merely the benefit of allowing web-entry, where maps can be drawn. Use of EWL on top of this is an additional economic advantage.


The last benefit to using electronic white-lining is somewhat counterintuitive. While EWL greatly improves efficiency, communication, and safety –thereby reducing damage– it is also critically important if a damage does occur. That’s because unlike physical markings on the ground, which are disturbed in the course of the excavation, EWL preserves a digital record of the dig site in its pre-marked condition, which can be referenced during investigations to determine liability and root cause. For damages like digging outside of the proposed excavation area, failure to mark within the dig area, and others, preserving the white-lines offers accident investigators, stakeholders, insurers, and others a wealth of information. PHMSA, the NTSB, and others should take a keen interest for this reason.


It’s Time for Nationwide Adoption of Electronic White-Lining

At the end of the day, the industry, states, and the federal government all agree that pre-marking is essential to damage prevention, that technology must be incorporated, and that the cost of damage must be addressed. Through the Common Ground Alliance, Electronic White-Lining has already been called out as a must-use technology for the ideal dig – that is every dig – by the year 2030. The benefits are clear today and the technology is available now. There is no need to delay, and stakeholders must act to integrate EWL into One-Call centers. Regulators and public officials should likewise seek opportunities to support this roll out through grants and stakeholder engagement as well as through regulatory action to establish electronic or virtual white-lining as a threshold first step in construction safety and damage prevention.


Read our recent 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.