Reimagining the Big Dig with Virtual Twins

Boston’s “Big Dig” was one of the most ambitious urban infrastructure projects in U.S. history. Officially known as the Central Artery/Tunnel Project, it aimed to address the city’s rampant traffic congestion by transforming an outdated and elevated highway into a more efficient, mostly underground network. An ambitious project, its construction took nine years longer than the original plan and cost 190% more than expected.

The Big Dig was plagued with problems. But what if it hadn’t been?

Today, large-scale urban projects can be carried out with foresight and precision that wasn’t possible even 10 or 20 years ago. Large urban undertakings, from expanding roadways to improving air quality to densifying ever-growing cities, can be carried out in virtual tests before ground is ever broken. By adding a virtual layer to the urban planning process, it’s possible to get things done in a more accurate and data-driven way. With the emergence of advanced technologies like virtual twins, cities can reimagine monumental projects like the Big Dig in a way that mitigates risk, optimizes efficiency and minimizes disruption.

Boston’s Big Dig: What went wrong?

Greenlighted initially in 1991, the Big Dig’s primary mission was to replace the central highway that cut through Boston with tunnels and new infrastructure designed to ease traffic flow and reconnect neighborhoods. It was an ambitious project, to say the least.

The initial budget for the project was set at $2.8 billion, but as construction progressed, costs ballooned to nearly $15 billion by its completion in 2007. But it wasn’t just the financial costs that plagued the Big Dig; time was another major casualty. What was intended to be completed in seven years stretched into more than 15 years.

Beyond dollars and deadlines, the project also encountered various other difficulties. Some were structural – leaks and a fatal ceiling collapse – while others stemmed more from publicity.

Long-winded infrastructure projects like the Big Dig have profound ripple effects. Dozens of structural abnormalities, including loose and missing bolts and gaps in the tunnel’s ceilings, were discovered in an investigation in 2008, just after the project was completed. Foot traffic decreased over the years in the area where construction took place, reducing patronage to local businesses. One long-standing restaurant in the North End neighborhood nearby was forced to close after 50 years; the owners eventually successfully sued the Massachusetts Department of Transportation, winning $8.5 million. Massachusetts taxpayers bore the brunt of some of the run-on costs of the project, too, getting hit in 2009 with gas tax increases to raise additional funds to cover its ballooning budget. The commonwealth’s transportation organization, the Massachusetts Bay Transportation Authority, is still reeling from the financial ruin of being forced to take on the project’s debt.

While the result of the Big Dig was eventually successful, it took a lot of trouble to get there. A project designed to innovate urban infrastructure left an aftermath of lessons learned the hard way. Urban planners today in cities around the globe don’t need to.

How could a virtual twin have improved the project?

Looking back, it’s easy to wonder how something like today’s technologies could’ve changed the course of the Big Dig.

Enter the concept of virtual twins. A virtual twin serves as a near-exact virtual replica of physical assets or spaces, encompassing structures, systems, environmental factors and their real-time interactions. Using Dassault Systèmes’ virtual twin solutions, cities today can plan, simulate and optimize urban infrastructure projects with a level of precision that simply wasn’t possible during the 1990s. Virtual twins can be constructed for every aspect of the urban development process, from projects dealing with energy grids, transportation routes, natural disaster mitigation plans and more. 

For the Big Dig, this digital technology would likely have resulted in a vastly different building journey, particularly in reducing both time and costs. Simulating construction phases virtually could’ve provided robust insights into pre-existing underground conditions in the urban environment, helping engineers predict challenges like soil instability, water leakage and outdated subterranean utilities far before breaking ground. Taking a model-based systems engineering approach would have enabled better foresight of issues like the gaps in the project’s ceiling panels. Such artificial intelligence-developed predictive modeling capabilities would’ve enabled recalibration of designs and strategies, potentially shaving years off the timeline.

Capital savings might also have been staggering. Virtual twins create a platform for cross-disciplinary collaboration, enabling engineers, urban planners and construction teams to identify inefficiencies before they translate into expensive reworks or accumulated delays. While urban infrastructure projects tend toward the expensive, it’s possible, through digital transformation, to pinpoint potential pain points with high price tags, as well as solutions to reduce them. Dassault Systèmes tools, for instance, enable stakeholders to test myriad “what-if” scenarios, ensuring an optimized outcome within budget constraints.

Most crucially, virtual twins excel at assessing the ripple effects of infrastructure projects on their surroundings. A predictive analysis of foot traffic patterns could have provided businesses with forewarning and allowed the local or state governments to develop a policy to support them during the construction phase. With the Big Dig impacting Boston on both structural and environmental levels, a digital replica would’ve offered valuable foresight into air quality changes, noise pollution and even the impact on local economies during construction. These factors could’ve been planned for proactively, limiting negative blowback.

Reimagining a new Big Dig

“If the Big Dig was happening today, everything would be planned and designed in the digital world first, effectively creating a “digital twin” of the project before a spade was put in the ground,” said James Gardner, head of insights and analytics at the New York-based construction consultancy firm Gleeds. One of the first steps in any large-scale construction and infrastructure project these days is, undoubtedly, making virtual models.

If the Big Dig could start again with virtual twin technology at its helm, it’s hard not to imagine a much more streamlined process and successful outcome – a hallmark of urban resilience, if you will. Project and city planners might’ve prepared for potential missteps—from disrupted traffic flow to environmental challenges—with corresponding mitigation strategies built into the design from day one. The implications of these preemptive actions would’ve rippled outward across Boston’s construction timeline, budget and community satisfaction.

Virtual twins could’ve supported the logistical integration of multiple real-time factors during construction rather than relying on piecemeal solutions to problems as they arose. Just imagine interactivity like what’s possible with augmented reality, indicating to relevant parties how each aspect of the project would fit together, or not. Coordination across team divisions—from environmental engineers to architects and communication teams tasked with informing the public—could’ve been seamless. This lack of instantaneous collaboration undoubtedly created bottlenecks, the likes of which are avoided when unified solutions like the 3DEXPERIENCE platform are harnessed in urban development projects like the Big Dig.

Additionally, the use of virtual twins could have aided in establishing greater transparency and stakeholder trust. Public updates could have been shared using dynamic 3D simulations, enabling Bostonians to visualize progress, challenges and adjustments with clear, digestible information. Citizen engagement could’ve been more possible, with city planners having access to the public’s views and insights as the project progressed.

Data gathered from virtual twins would also have allowed for continuous adaptation throughout each phase of the project. To be an agile smart city in the 1990s was still a dream, not a reality that’s much more possible in the 21st century. For example, as unexpected conditions, these systems could’ve adjusted workflows to maintain budget while adhering to the overall schedule. It’s inevitable in a project of such scale and magnitude that problems will arise, sometimes over and over again, and the ability to overcome them with precision is an essential factor in success.

It’s not difficult to see how this digitally-enhanced, proactive and innovative solution would’ve resulted in a quicker final product with fewer hiccups along the way.

Inspiration for cities worldwide

While the Big Dig remains a somewhat cautionary tale, it’s also a source of inspiration grounded in lessons for cities across the globe.

First, consider what the Big Dig resulted in, physically speaking. Moving the highway underground resulted in a more vibrant, green space: a success in terms of developing a usable, beautiful urban space. The move, a boon for urban sustainability projects, has been made elsewhere, too. An expressway in Portland, Oregon, was removed, and in its place, a waterfront park was erected; a highway in Seoul, South Korea, was demolished, and a stream now flows where cars once drove. In both cases, the projects had positive environmental outcomes, reducing urban heat island effect, removing pollutants from the air, and in the latter, providing flood protection.

To look at the potential for technology-infused urban development and infrastructure projects, the Big Dig offers lessons to be learned. By adopting virtual twin technology, urban areas can undergo large-scale initiatives free from many of the pitfalls that slowed down Boston’s vision.

Be they focused on updating aging infrastructure, implementing sustainable development projects, coping with rapidly expanding populations or tackling any number of urban challenges, the potential of virtual twins knows no bounds. Urban planning tools, for instance, offer the ability to streamline projects using simulations that accurately reflect the evolving complexity of real-world environments.

Virtual twins can also lend themselves to ambitious endeavors beyond infrastructure. Imagine hyper-efficient public transport systems connected seamlessly to pedestrian zones, energy-saving smart buildings and resilient networks designed to adapt dynamically to climate change. Combined with emerging technologies, like augmented reality and artificial intelligence, virtual twin technology empowers cities to plan comprehensively, mapping the interplay of resources, technology and communities with an unprecedented level of detail and foresight. This kind of digital transformation in urban governance exemplifies an innovative solution to build a smart city that works for its citizens.

By learning from Boston’s experiences, cities have a chance to rethink their urban innovation strategies, harnessing virtual twins as both safeguard and guide.

Shaping the future of urban planning

The Big Dig was a bold vision, ultimately proving that with enough determination, even urban landscapes can undergo profound transformation. What now stands where the interstate once did is a green highway of sorts, an urban space filled with trees and plants, home to cultural activities, pedestrian commuters, art installations and more. Reimagining the initiative in hindsight with the power of virtual twins elevates the original vision to a whole new level, enabling urban planners to solve problems before they start, engage with communities at every step and unlock long-term value for future generations.

With the digital technologies available today, it’s possible to conceive of all the urban challenges that could have been solved with virtual twins and the simulation and modeling capabilities they have. Would the Leaning Tower of Pisa still lean? Would Boston’s Hancock Tower have lost so many windowpanes? It’s hard to know exactly, but it’s easy to imagine the ways in which testing construction, engineering and design plans in a virtual twin could reap more successful outcomes.

By integrating virtual technology into infrastructure projects, stakeholders can create faster, smarter and more sustainable cities that truly thrive. Adopting an approach that aims to enact urban innovation with digital twins can make cities better for the environment, for citizens and for the future as a whole.