Part of Northwest Hydraulic Consultants (NHC), Lasalle|NHC is a Montréal-based consulting firm offering services in the fields of hydraulics, applied fluid mechanics, and water resources. It has significant expertise in the use of physical hydraulic scale models and computer modeling, including for the design and construction of hydropower facilities. In this interview, Lasalle|NHC President Marc Villeneuve tells us about the company’s experience and specialization and its work securing and managing water supplies now and into the future. 

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Hydro Leader: Please tell us about your background and how you came to be in your current position. 

Marc Villeneuve: I initially learned about Lasalle|NHC through a lab visit I made as a McGill University student in the late 1980s. I approached the company after completing my graduate studies and was hired for a short-term contract. It turns out that more than 30 years later, I’m still with the company. I was fortunate enough to be directly involved in the hydraulic optimization of most of the projects developed by Hydro‑Québec, from phase 2 of the James Bay Complex to the more recent Romaine projects. I’ve also worked extensively in recent years with BC Hydro on the Site C clean energy project and Ontario Power Generation on the Lower Mattagami River project. What started as a short-term contract turned out to be more than 30 years of active work not only in the hydro industry but also in hydraulic structures and water resources more generally. 

A scale model of Long Lake Dam, located near Spokane, Washington.

Hydro Leader: Please tell us about Lasalle|NHC. 

Marc Villeneuve: Founded in 1956, our company is now part of NHC, which employs more than 200 water resource specialists in offices located across the United States, Canada, Asia, and Brazil. Initially known as the LaSalle Hydraulic Laboratory and part of the French Consulting firm Sogreah (now Artelia), the company became independent and employee owned in the mid-1970s. Our merger with NHC in 2014 created one of the largest networks of water resource specialists in North America. NHC will celebrate its 50th anniversary in 2022. The combination of these two companies represents considerable hydrotechnical experience. 

Our mission was and still is to provide advanced expertise and modeling services in hydraulics, hydrology, and fluid mechanics. With the sustained development of hydropower in Québec over the last 60 years, Lasalle|NHC’s emphasis was previously more on hydro projects and hydraulic structures. The merger with NHC has really widened our scope of services, and we are now very active in other areas, such as urban hydrology, floodplain studies, and environmental hydraulics. 

Hydro Leader: What was the impetus to merge the two companies? 

Marc Villeneuve: First, physical hydraulic modeling is a rather specialized field, with a cyclic and variable market, and both companies were often competing for the same projects. It was clear that it would make more sense to collaborate both technically and corporately to develop a more efficient entity. The other benefit was also to allow both parties to diversify geographically and to be present on both sides of the continent. 

Hydro Leader: What does it mean that NHC is employee owned? 

Marc Villeneuve: The organization is entirely owned by about one-third of its more than 200 employees. This broad base of ownership ensures strong employee engagement in the company’s future and communicates to all technical staff that ownership is an achievable goal. Importantly, this broad ownership also promotes the succession of the company’s management team, which is often problematic in small and mid-size consulting firms. 

Hydro Leader: Are most of NHC’s 200 employees engineers? 

Marc Villeneuve: Yes, most are engineers who specialize in various areas of water resources, but they also include many geoscientists: geomorphologists, geographers, environmental specialists, and experts in geomatics. We have the whole range of expertise that is required to cover the full spectrum of surface-water-related studies. 

Hydro Leader: Where is most of your work located? 

Marc Villeneuve: Our offices in Washington State and California are busy on U.S. projects, while our British Columbia, Alberta, and Québec offices focus more on Canadian work. Our main market remains North America, but we also have a team of specialists with a strong presence in South Asia, notably in Bangladesh. There, we are involved in flood management, drainage, irrigation, and river training. Currently, our highest-profile work in Bangladesh relates to the construction of the 6‑kilometer bridge across the Padma River. Our office in Brazil has also been growing in recent years. 

Hydro Leader: Who are your typical clients? 

Marc Villeneuve: The large hydro and water resources markets in North America are primarily run by public institutions and agencies and various level of government. Companies involved in hydropower production, such as Brookfield and Rio Tinto Alcan, are also important clients for us, as are private developers of mini and small hydro facilities. 

Because of the specialized nature of our services, we are often hired as subconsultants by larger international multidisciplinary engineering firms for advanced services or modeling in hydrology and hydraulics. 

A scale model of a spillway.

Hydro Leader: Does your work typically involve designing new structures or redesigning and rehabilitating existing ones? 

Marc Villeneuve: We do both. In Canada for example, the last few decades have seen the development of multiple large new hydropower projects. But we expect projects in the near future to focus on the refurbishment and upgrade of existing hydro installations, both in the United States and Canada. The scope of our services does vary between our various offices and markets. In Québec, for example, Lasalle|NHC still mainly concentrates on hydraulic and hydrologic modeling work, while at our U.S. offices, the actual design and construction of hydraulic structures makes up a clearly increasing share of work. 

Hydro Leader: Would you tell us more about your numeric and physical modeling work and how the two relate to each other? 

Marc Villeneuve: With the current state of the art in hydraulic modeling, the two approaches should be fully complementary. Physical modeling should not be used to systematically repeat all the advanced numerical computational-fluid-dynamics (CFD) modeling that has already been performed in previous phases of a project; ideally, it should be used to further investigate issues and problems for which the results of numerical modeling still raise uncertainties, which may include cavitation, energy dissipation, detailed rating curves for spillways, vortices at power intakes, and high headgate vibration. 

An important problem in hydraulic modeling is the lack of knowledge of what a numerical model can really predict with accuracy and minimal risks. In our digital age, many clients, and unfortunately many consultants, see no limit to the types of problems that a numerical model can tackle. Unfortunately, in spite of the ongoing progress in computing speed and software development, there are still challenging issues in the numerical modeling of complex flow phenomena. The physical modeling approach obviously also has drawbacks, but the much longer experience we have with model-prototype correlations often provides a level of confidence that can be difficult to achieve even with the most advanced numerical models. It’s unfortunate that many engineers, especially in the younger generation, have lost the sense of the advantages still offered by the work that is done in a hydraulic laboratory. 

When I started my career in the late 1980s, having done graduate studies in numerical modeling, I was fast to predict the rapid demise of physical modeling. Thirty years later, it is clear that both approaches should still be part of the hydraulic design process. The progress made in CFD modeling is truly amazing, but there is still a need for a physical model in many instances. Companies like Lasalle|NHC have the benefit of being able to offer the modeling approaches, numerical or physical, that are best suited to the nature of the problems being studied and the needs of their clients. 

Hydro Leader: Would you tell us about the labs you use for physical modeling? 

Marc Villeneuve: The term lab can be misleading, because people think of a chemical, research, or medical lab. All the NHC labs (in Montréal, Vancouver, Edmonton, and Seattle) are warehouses with floor areas of 10,000 square feet or more. The scale and size of the physical models constructed within these spaces usually make them look more like small

construction projects than typical laboratory installations. The models have to be large enough to minimize so-called scale effects, which are linked with the viscosity and surface tension of the water and can lead to inaccuracies in the modeling results and their transposition to the prototype (that is, the actual, full-scale structure being studied). 

Physical hydraulic modeling as we know it today has its origins in the mid-nineteenth century. Nevertheless, the way we construct and operate these models is constantly evolving. For example, the use of 3‑D printers and the constant development of new flow sensors and data acquisition systems have completely changed the way we perform physical model studies. 

Hydro Leader: How do your work and expertise differ from those of your competitors, and why are there so few firms specializing in this area? 

Marc Villeneuve: We live in an age in which the trend for engineering companies is to merge, consolidate, and become bigger and more multidisciplinary. For more than 50 years, NHC and Lasalle|NHC have been concentrating on hydraulics and specialized water resources issues. While large engineering firms may have substantial hydraulics or water resources departments, that is generally not the same as having a team of 200 people fully devoted to these areas. We are a specialized, niche company in a world of consolidated, multidisciplinary companies. That gives us a clear edge in many types of studies and projects. 

The other big difference is the in-depth hydraulic experience gained by our specialists on physical models and experimental work. I think it gives us a perspective that would be difficult to develop if we had only been focusing on numerical modeling. In a sense, we treat both modeling approaches in a similar way: as specialized disciplines that must rely on experience, not as a commodity service that simply requires a set of modeling tools. 

Hydro Leader: What is the public perception of hydropower? 

Marc Villeneuve: Over the decades since the start of my career, the perception of hydropower has gone through turbulent times. When I was in university, hydro was still considered an almost-perfect renewable source of energy. With time, large hydro projects became better known for their major environmental impacts than for their renewable energy. In a course I taught on hydraulic structures at McGill University, some students almost felt guilty as they entered the field of hydraulic engineering. 

More recently, this perception has improved slightly, probably because of the increased awareness of climate change linked with the use of fossil fuels. Especially in the case of megaprojects, hydropower has certainly not regained the status it had in the 1960s and 1970s, but I think there is still an interesting shift. To me, the recent signing of a 25‑year contract between Hydro‑Québec and the State of New York for the distribution of hydro energy is a sign of that shift. 

Hydro Leader: How do the changes in water supply caused by climate change affect your work? 

Marc Villeneuve: The effect of climate change on the safety and sustainability of water supplies is already a central service area of all the NHC offices, especially those in California. Right now, a lot of the studies being performed in this area deal directly with the basic hydrological cycle: the change in weather patterns, the occurrence of increased or reduced rainfall and runoff, and so on. In the hydro sector, we are also seeing projects linked with an increase in the range of operation at existing plants, notably for exceptionally low reservoir levels. It is interesting to note that Lasalle|NHC had already performed such studies in the early 1990s, during a period of very low runoff affecting Hydro‑Québec’s reservoirs. Studies like that, aimed at increasing the range of operations of hydro plants, should become more important, not only in the context of climate change but also to save energy and optimize the operations of existing facilities. 

Other important issues related to climate change, like sea-level rise and the reduced presence of ice in Nordic coastal regions, are already major study areas of our coastal engineering and modeling teams. 

Hydro Leader: What is your company’s vision for the future? 

Marc Villeneuve: Our vision for the company is to remain at the forefront of water resources engineering and science by strengthening existing operations and strategically expanding our services. 

Climate change and its potential threat to public safety and water supply will clearly become a priority not only for our company but also at a much broader, collective level. Population expansion into floodplains, coastal zones, and other vulnerable ecosystems will also raise important issues around the human-water interface. 

On a more technical level, the future of water resources should also see the further development and application of smart hydraulic infrastructure, into which forecasting and real-time monitoring are fully integrated—something that is already present in the field of hydropower. Such concepts are likely to be extended to smart cities and communities. 

Marc Villeneuve is the president of Lasalle|NHC, the Québec subsidiary of Northwest Hydraulic Consultants. He can be contacted at For information about NHC’s U.S. operations, please contact Erik R. Rowland, PE, the president of NHC Inc., at