Luis Montestruque, ND Ph.D. ’04 (electrical engineering), is a pioneer in the field of smart water systems. For more than two decades, he has helped utilities improve water resource management, reduce flooding, and minimize combined sewer overflows. He is the founder and CEO of HydroDigital—a South Bend company that designs, deploys and supports smart water systems across the U.S. and internationally.
In this conversation, Montestruque discusses the evolution of smart water technology, the role of green infrastructure, his company’s recent work in the U.K., and the forces that have shaped his engineering career.
What challenges do the utilities HydroDigital works with typically face?
Virtually all our clients have aging infrastructure. We have worked with some utilities that have wooden water pipes that date back to the civil war era.
Our solutions do not replace the need to update aging infrastructure. Our solutions help utilities better manage their existing infrastructure. We offer one tool in a toolbox of approaches to manage sewer systems.
While sometimes it’s necessary to build new infrastructure, we’re happy when we find ways to avoid spills or overflows that are 10 or even 100 times less expensive than traditional gray infrastructure—such as underground storage tanks.
How have your smart sewers evolved over time?
Back in the early days, the process of identifying, designing, and launching a smart sewer program was labor-intensive and took many months. Machine learning tools have helped us accelerate this process so that it now takes days—or even hours to do the same work.
Also, more powerful cloud computing has helped lower the cost of these programs, so it’s possible for water systems of all sizes and economic resources to take advantage of smart sewer systems.
The cost of internet of things (IoT) sensors has decreased to the point that utilities can collect more data about how their water systems operate. This data can then be used to train machine language models that help better predict what will happen during the next storm event.
In 2008, South Bend was one of the first smart sewer systems in the world and considered one of the most densely monitored sewer systems in the US, if not in the world, with 150 level and flow sensors. Fast forward to today and there are utilities with thousands or even tens of thousands of sensors deployed.
Your smart sewer systems employ “digital twins.” Could you explain what they are?
In our application, the term digital twin means a system that combines the use of a model with sensor data in real time. The sensor data gives the digital twin the ability to understand current conditions while the model projects the future evolution of the system under different operational conditions.
Do green infrastructures (e.g. rain gardens, street trees) ever play a part in your smart water systems?
Yes, all the time! When our team worked in South Bend, we used the digital twin to find all the possible combinations of grey, green, and smart infrastructure that provided the city with a compliant solution that was both cost effective and equitable.
Many of the great green spaces around South Bend were originally slated for the construction of tanks and rapid treatment facilities. We are proud to say that we were able to use green infrastructure in those areas.
HydroDigital is now working in the United Kingdom. What are some of the differences between the U.S. and U.K. in terms of their sewer systems?
U.S. utilities have been working on addressing combined sewer overflows (CSOs) for many decades. Today, most of its 778 utilities with combined sewer systems have programs in place to address CSOs. While we continue working with U.S. utilities to maximize the investment made in new infrastructure, U.K. utilities have only in the last few years experienced enormous regulatory and public pressure to solve their overflow problems.
While the U.K. has been slower in building new CSO-focused infrastructure, the rate of adoption of new technologies is many times faster than the U.S. The utilities in the U.K. are also private regional utilities. There are 14 regional wastewater utilities in the U.K., while the U.S. has more than 16,000 utilities.
Did your experiences at ND help prepare you for the engineering you do now?
100% percent. My research at ND with Prof. Antsaklis was focused on networked embedded systems which was a great foundation for the technology that we use today. Close to graduation, Prof. Lemmon introduced me to Prof. Tally—then in Notre Dame’s civil engineering department—and his graduate student Tim Ruggaber [ND M.S. ‘06]. These connections encouraged me to apply embedded control to sewer systems. Tim became my collaborator in tech development, and he’s now co-founder and chief delivery officer at HydroDigital.
Notre Dame also developed my skills as an entrepreneur. Investors from Irish Angels were key to my success. I was also able to work with the Mendoza Business School and partnered with then MBA student, Dr. Naunihal Virdi [ND MBA ‘05], to participate in the McCloskey New Venture Competition.
Was there anything about your early life that helped to shape your career?
I was born in South Bend while my dad was getting his Ph.D. in physics, but I grew up in Lima [Peru]—a mega city located in what is one of the driest deserts in the world with less than 0.2 inches of rain per year. The city gets its water from a river that makes the St Joseph River look like the Mississippi in comparison.
Today, 26 years after I left Peru, I’m proud to be working with utilities in Peru to help them better manage their water systems.
How can engineering students be better trained to deal with current challenges in the workplace?
It’s important for engineers to learn how to maintain the necessary grit and persistence to push through difficult problems. As an engineer, you need to have confidence that you can and will solve even the toughest problems.
And, ultimately, I think, it’s the values and principles that an engineer grew up with that will shape our future world.
—Karla Cruise, Notre Dame Engineering
Hero photo: Montestruque (left) and Tim Ruggaber in North East England where HydroDigital worked with Northumbrian Water to install a smart sewer system.