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HNTB’s Sanja Zlatanic: a Happy Mole

By Richard Massey

There’s no doubt about it. Sanja Zlatanic, Senior Vice President and Chair of the HNTB National Tunnel Practice, loves mega-projects. Confronting epic problems and managing the associated risk is what she does best. Existing constraints, the concerns of communities and stakeholders, multi-billion-dollar price tags, and meticulous team building are all part of the package when you’re boring tunnels under cities or bodies of water. New York, Baltimore, Los Angeles, San Francisco, Seattle, and Istanbul – Zlatanic has made her name working on the industry’s premier tunneling projects over the last three decades. But if you want to get a true measure of her ability to handle whatever is in front of her, you might as well go back to the early years, when the University of Belgrade graduate was just starting out. She was in Iraq on a government contract in 1990 when Saddam Hussein invaded Kuwait. She and the team were not allowed to leave until their project was done, so they went into overdrive, closing out a four-month job in just 21 days. Zlatanic returned to Belgrade, but at that time the former Yugoslavia was disintegrating into war. She and her husband Jusuf fled, obtaining their visas in Budapest, Hungary before heading to the United States. Once in New York City, Zlatanic hunkered down in a small apartment for three months, consuming language tapes, books, and TV shows to learn enough English to get through a job interview. It worked. In 1992 she was hired by Parsons Brinkerhoff and was there for nearly 20 years, mastering the tunneling trade, before joining HNTB in 2011. With an office on the 58th floor of the Empire State Building, Zlatanic has a nice view of the Freedom Tower and the Statue of Liberty, fitting reminders that she’s living her American and engineering dreams. For dreams to come true, however, they must be chased, which is what Zlatanic did when, as the borders of her homeland closed, she made her great escape.

“There is no event on the job that can stress me any more than that,” she said. “I was prepared later in life for anything.”

A Conversation with Sanja Zlatanic

Civil + Structural Engineer: Your resume speaks for itself. You have been associated with some of the biggest and most important tunneling projects in the United States for the last 30 years. What draws you to these mega-projects?

Sanja Zlatanic: Primarily, it’s the ability to work with architects and planners to create a practical project configuration that can be materialized and constructed within the constraints of actual subsurface conditions, often in a dense urban environment.

It is a real thrill to conceptualize large and complex underground undertakings while working with existing project constraints; either overlying buildings and facilities that need to remain fully operational all the time, or adjacent rail or road operations that must be in full service at 5 a.m. every morning. Also, it can be a challenge finding ways to explain the project to impacted businesses and communities at every step, incrementally, demonstrating that safety would never be compromised at any point during construction and that impacts are measured, sensitive to everyday life of the communities, and of a temporary nature.

A notable example of a “grand” underground concept is the East Side Access project that extends the Long Island Rail Road from its main line in Queens into a new station under Grand Central Terminal on Manhattan’s East Side. In the beginning, the project was envisioned as a ‘shallow’ option directly connecting to the lower level of Metro North Railroad. We realized early on that such a concept would have significant impacts on several high-rise buildings along Park Avenue, some of those historical, and worked with the project owner to make it an underground project while reducing impacts. We envisioned the project in a form of two parallel ‘twin’ caverns housing four platforms each and a mezzanine in-between. Cross-passages and escalator-ways connecting these two large facilities were placed directly below the streets minimizing effects to the overlying buildings. I recall long sessions our team held with the lead architect to plan these gigantic underground spaces. They needed to meet operational, safety, and maintenance requirements, as well as midtown Manhattan’s environmental constrains during construction. It was like “building a ship in a bottle.” Most of the tunnel spoil removal was going through the Queens access shaft a few miles away. The project, clearly the largest undertaking in New York City in a long time, is expected to open in a few years so the opening day is not that far away.

Another example of grand conceptual thinking is Santa Clara Valley Transportation Authority’s BART Silicon Valley Extension, Phase II, where we suggested a single bore concept to minimize construction impact through downtown San Jose. This is the first time this approach is being used in the United States. VTA as the owner and BART as an operator had demonstrated great stamina and willpower to work together to resolve technical challenges. They jointly conceived an operational scheme that responds to the needs of both users and operators. Working with savvy program managers on both sides is very helpful; they saw the value of the project from the beginning and worked tirelessly with the engineering team, side-by-side, to explore all challenges and potential paths to solve them.

C+S: What’s your message to women who are thinking about entering the engineering profession in general, and tunneling in particular?

SZ: Women play very important roles in the tunnel industry. I have noticed throughout my career that teams that have the benefits of diverse participation, especially when solving complex challenges and exploring innovations, are generally more productive. A few decades ago, there were a handful of us that had made this career choice; however, today many more young female professionals are interested in tunnels and underground engineering. This has been very refreshing and encouraging. They will find this industry supportive and rewarding. I have never met a woman who expressed a regret about being in the tunneling industry, so I guess this makes it a “happy” career choice as well.

C+S: You’ve said New York turned out to be a great proving ground for you as many large tunnel projects took place there early in your career. Looking back at that time, what were the most important career lessons you learned?

SZ: Tunneling and underground projects are among the riskiest engineering practice areas; solid engineering judgement and practical solutions that always have safety as a primary concern are paramount. Throughout the years, I have learned that the only way to successfully conquer great challenges is to rely on a team contribution, and having the courage to pursue one’s own vision and convictions. Often it is not easy, but while practicing perseverance, respect, and camaraderie that are very typical for the tunnel industry, it is possible. Courage is a big component as well.  One should speak his or her mind, especially when having an idea that may move a project forward.

C+S: As you well know, tunnel projects are risky. How does the presence of such great risk inform the decisions you make when working on a project?

SZ: Dealing with risks is challenging in every profession, and this is especially true for the tunnel industry. Risks, if not well understood and managed, may lead to major events that could impact lives, material property, and even regional economies. Therefore, risk management is one of the most important subject matters on tunnel projects that needs to be addressed continuously, from the very onset of the project to its closure. Risk register is a living document that not only defines different areas and levels of risk, including technical, but recognizes parties that are best equipped to handle various risk elements throughout the life of the project. Those parties could be designers, owners, or contractors. Recognizing early technical and other risks and having a plan to address them is a must in our industry. The best way of dealing with risks is their avoidance, whenever possible. In this realm, establishing the right project configuration and understanding the subsurface conditions and environmental factors for practical construction often is a crucial step. Dealing with risks in construction that could have been avoided in design is the wrong way to manage the issue.

C+S: The Alaska Way Viaduct Replacement was transformative for Seattle. The project also used “Bertha,” an extremely large boring machine. The tunnel opened to traffic last year. With the Seattle project in mind, what is the future of tunnels here in the United States and abroad, and how will they shape the urban landscape?

SZ: Rapid urbanization and growing migrations from rural to urban areas have been worldwide issues for a few decades. It is expected that in less than three decades about two-thirds of the world population will live in cities. The cities would need to double in size to accommodate such growth. This issue is much more pronounced in the United States since the nation’s urban population growth already outpaced the overall growth over a decade ago. In 2015, about 83 percent of the total population in the United States lived in urban areas. It is being projected that in 2050 this number will be over 87 percent. Therefore, there is a real urgency to make our own cities ready for such urban population increases. The issues of livability, quality of life, and effectiveness of transportation networks are of special concern. Cities are finding their own unique ways in addressing those issues. Seattle is a notable example.  The city adopted utilization of a large double deck tunnel beneath downtown Seattle to improve mobility. With the decision to demolish the old viaduct, they brought the shoreline closer to their people and communities. Bertha, at the time the largest bored tunnel machine in the world, completed her journey on a high note and with exceptional performance. Generally, recent advancements of tunneling technologies permit better utilization of underground space and allow surfaces to be considered for more noble uses that bring significant improvements to quality of life in overcrowded urban dwellings.

C+S: Tell us about your work with the Associated Research Centers for Urban Underground Space (ACUUS).

SZ: ACUUS was established in 1996 and was subsequently incorporated. The organization has an important non-governmental function; it establishes a unique world “coalition” of experts that designs, plans, analyzes, and decides upon the sustainable use of urban underground space. It was designed to connect public and private sectors with academia’s latest research and related findings in terms of the use of underground space. Also, it created a platform for exchange and cooperation. As Secretary General, and a member of the ACUUS Board, I am active within this framework and able to learn and transfer my experiences, especially in the realm of integrated planning and design; sustainable approach to the environment; as well as safety and technical innovations. Embracing disruptive technologies to help resolve the issues of urbanization and overcrowding, and finding ways to better plan and utilize urban underground space for a purpose of freeing surface resources (already very limited), is another realm ACUUS is ready to tackle.

C+S: You grew up in the former Yugoslavia and fled the war there in 1991. These days, you have an office in the Empire State Building. That is a remarkable journey for a variety of reasons, and is symbolic of the American Dream. What role did engineering and tunneling play in this incredible life/career arc?

SZ: Yes, you are right – my engineering dream had pretty much overlapped with my American dream. I tend to associate my growth as a professional and as an American primarily to the hard work, persistence, tremendous will power to continue working on self-improvement, trust in the professionals I am working with, and above all, with my family that has always supported me through this journey. Starting with a well-known tunneling company, learning tools of the trade and how, when and where to use them, as well as being able to work alongside the biggest names in the U.S. tunneling industry, played a big part in my career.

C+S: What was the most challenging project you have ever worked on and why?

SZ: Every project has its own challenges. Possibly the most challenging one was, sadly, one that was cancelled – Access to Region’s Core, the tunnel project that is being revived in the form of the Gateway project. This project had all the great technical challenges one would look for in a tunneling project, as well as challenges of working with multiple agencies and stakeholders. All of it is to be revived in the new project the industry has been waiting for. Applying lessons learned and previous experiences, and working with tunnel industry veterans addressing similar challenges will be refreshing. I hope it gets to that point soon.

C+S: Building great teams. What’s the secret?

SZ: Trust, trust, trust. Also, technical competence, strong will to learn, and having open and cordial relationships with team members while understanding their issues and aspirations.

As chair of HNTB’s National Tunnel Practice, I am leading an exemplary group of national tunnel experts that practice technical excellence, demonstrate a high level of professional integrity, and serve as thought leaders and mentors for younger generations of tunnel professionals. I am very proud of them all.

C+S: Are you recognized in Belgrade, and do you return there for personal and/or professional reasons?

SZ: I recently started reviving old partnerships and making new connections through activities with ACUUS. That part of Europe has some of the world’s brightest and bravest minds and I certainly hope it will soon be more open to worldly exchanges.


AMTRAK – Baltimore and Potomac (B&P) Tunnel in Baltimore, Maryland

Preliminary engineering studies and environmental analyses of the B&P Tunnel to improve rail service, reliability and address a longstanding bottleneck along Amtrak’s busy Northeast Corridor (NEC).

LA Metro – Crenshaw/LAX LRT Line, Los Angeles, CA

Design of underground segment of this $2B design build program for HNTB as a lead designer of a DB team.

MTA – Long Island Rail Road, East Side Access/ Grand Central Connection, New York, NY

Design manager who led the design development of the Manhattan segment deep station alternative and was responsible for the delivery of the final documents that resulted in the selection of the deep station scheme for this $7.6 billion project.

MTA Bridges and Tunnels (TBTA), Brooklyn Battery Tunnel Wall and Ceiling Rehabilitation, New York, NY

Project engineer during the project’s construction stage, this project for MTA Bridges and Tunnels comprised tunnel ceiling rehabilitation, liner repair for damage caused by water leakage and roadway lighting improvements for the 9,717-foot-long (3,000-meter-long) Brooklyn Battery Tunnel – the second longest underwater crossing in the U.S. – connecting lower Manhattan and Brooklyn.

Republic of Turkey Ministry of Transport, Istanbul Strait Road Crossing (Eurasia) Tunnel, Istanbul, Turkey

Category 3 structures, systems and facilities for this $1.35B Istanbul Strait Road Tube Crossing project of 14.5 km in length that includes 5.4 km of road tunnels and 3.4km Bosphorus Strait Crossing double-deck bored highway tunnel 13.2m in diameter, and 2km Asian and European side tunnel approaches (roadways, toll plazas, ventilation and system buildings and facilities).

San Francisco Municipal Transportation Agency, Central Subway Project – Underground Stations, San Francisco, CA

Underground stations of San Francisco’s Central Subway project as part of a tri-venture on this project that consists of 1.8 miles of twin tunnels 20-feet in diameter and three underground stations at a cost of $1.58 billion.

Washington State DOT – Alaskan Way Viaduct Replacement

Panel and technical oversight lead for $2.4 Billion design build project of 2.1 miles bored tunnel that replaces the Alaskan Way Viaduct along the central Seattle waterfront.

The Zlatanic File

Sanja and husband Jusuf, a gastroenterologist in New York, have two sons, Viktor and Matthew.

Richard Massey is a freelance writer based in Northwest Arkansas. He can be reached at wordpower.richard@gmail.com.