Proceedings of the Canadian Society for Civil Engineering Annual Conference 2024, Volume 9

Table of Contents

1. Frontmatter

2. A State-of-the-Art Review on Dam-Break Risk Assessment: A Decade of Methodological Insights

   Reza Ghanatian, Mauricio Dziedzic

   Abstract

   This paper presents a comprehensive state-of-the-art review of the risk assessment associated with dam breaks, focusing on advancements in the field over the last decade. This study investigates the risk assessment methodologies that have been employed to evaluate the likelihood and consequences of dam failure, with a primary emphasis on four common models: Probabilistic Models, Fault Tree Analysis (FTA), Event Tree Analysis (ETA), and Failure Modes and Effects Analysis (FMEA). The review encompasses an extensive survey of over 50 recent articles, shedding light on the parameters considered in these studies, as well as the types of dams and failure modes analyzed. By synthesizing and critically examining the findings from these research endeavors, this study identifies gaps in the existing knowledge base and offers insights into future research directions in the domain of dam-break risk assessment. This review not only provides an up-to-date summary of the state of the art in the field, but also offers a valuable resource for researchers, practitioners, and policymakers engaged in dam safety, disaster management, and risk mitigation, ultimately contributing to improved strategies for safeguarding both human lives and critical infrastructure in the face of potential dam failures.

3. Multi-objective Optimization for Renewal Planning of Sewer Systems Under Changing Climate

   Kayhan Alamatsaz, Hamidreza Shirkhani

   Abstract

   The maintenance and management of sewer networks have become a growing challenge for municipalities. Sewer inspection and rehabilitation efforts are costly and often are constrained by limited budgets. Moreover, rapid urbanization, climate change impacts, and aging can increase the likelihood of more frequent and uncertain sewer pipe failure. In a reactive management approach, the assessment and maintenance of sewers are usually neglected until a failure occurs. This reactive approach can lead to significant consequences with substantial socio-economic and environmental costs. Therefore, a proactive management approach becomes essential to preventing these costly consequences while minimizing the cost of interventions. Municipalities face increasing pressure to adopt proactive management approaches to maintain acceptable conditions, performance, and service levels for their sewer networks. Proactive management requires the development of optimal renewal planning strategies that are typically characterized by conflicting objectives. This necessitates the utilization of an efficient and robust multi-objective optimization model. The optimization model will provide near-optimum renewal plans over a planning horizon that determines the timing and renewal strategy for each pipe, including repair, replacement, or resizing. Due to the complex nature of sewer system rehabilitation planning and the large number of pipes, the solution space expands significantly, making searching for the optimal solutions challenging. Moreover, the number of objective functions can influence the problem's complexity. Although using fewer objective functions can facilitate the optimization process, it requires aggregating various objective functions with different dimensions, potentially overlooking certain problem perspectives. This study will examine a proposed NSGA-II method to solve the problem. The outcome of this research has the potential to provide decision-makers with more accurate and effective near-optimum renewal planning strategies. These strategies are essential for the proactive management of sewer systems that can lead to effective stormwater management, enhanced flood resilience, and successful adaptation to the impacts of climate change.

4. Numerical Simulation of Microplastics Transport in Saguenay Fjord Using Ray Tracing Particle Tracking Model

   Mohammad Ghazizadeh, Abolghasem Pilechi, Philippe Lamontagne

   Abstract

   Microplastics are ubiquitous pollutants in oceans, rivers, lakes, estuaries, and coastal areas, and pose a serious threat to aquatic ecology and natural ecosystems. Predicting the fate and transport of microplastics in these water systems, which are typically driven by complex hydrodynamic patterns, is essential for understanding accumulation zones, pathways, and potential sources and necessary for decision-making, remediation, and recovery activities. Numerical models based on the Eulerian–Lagrangian approach have effectively demonstrated robustness in predicting the evolution of microplastics in aquatic environments. An innovative three-dimensional (3D) ray tracing (RT) model over unstructured grids to simulate the movement of particulate matter in water is utilized in this study (Ghazizadeh et al. in Comput Phys Commun 307:109423 (2025), [1]). This model (CaMPSim-3D) has been integrated into the 3D numerical particle tracking model (PTM) previously developed at the National Research Council of Canada for predicting the fate and transport of microplastics in rivers and coastal areas. The PTM has shown superiority in terms of computational efficiency compared to the existing models and is not reliant on mesh size. Additionally, the upgraded model is able to account for vertical changes in particle coordinates caused by tides. Furthermore, the PTM is capable of considering particle interactions with the shoreline and seabed during the tidal cycle by applying wet-dry conditions, particle sedimentation, and the beaching and washout processes. In this study, the PTM is applied in a real-world case study to predict the transport and accumulation zones of microplastics in the Saguenay Fjord. Up to 20 million particles are released in the Fjord. Particle concentration in 2 zones is studied and the normalized concentration over the entire computational domain is demonstrated.

5. Determination of Hydraulic Parameters of a Laboratory-Scale Smooth Surface Spillway Using Numerical Modeling

   Elaheh Motahari Moghadam, Ali Saeidi, Javier Patarroyo, Alain Rouleau

   Abstract

   Hydraulic erosion in dam spillways poses a significant threat to dam infrastructure, requiring the evaluation of hydraulic and rock mechanic parameters. In this study, the hydraulic parameters of a smooth surface unlined spillway were evaluated using Computational Fluid Dynamics modeling (CFD) based on a 1:40 reduced-scale model of the Hydro-Quebec Romaine 4 spillway. While physical experiments can yield reliable results, they are costly and subject to scale effects and several errors, including on kinetic estimates. Numerical simulations, on the other hand, offer a cost-effective and accurate approach. Accordingly, the Flow3D software, which employs the Finite Volume Method, was used to properly anticipate flow behavior and 3D fluid motion patterns using the renormalization group turbulence model with the volume of fluid approach. Measurements along the channel demonstrate a reasonable tendency whereby velocity increases from upstream to downstream of the spillway. In addition, we observed a smooth and quasi-linear decreasing water height in the open channel. The study offers an understanding that can help future hydraulic structure design by determining the critical flow parameters along the spillway.

6. Effects of Fluid Properties on Fluid Entry of Free-Falling Disk

   Mohammad Amin Ebrahimi, Amir Hossein Azimi

   Abstract

   The characteristics of fluid entry of free-falling disks in stagnant ambient have many applications in environment protection and engineering design. To further study the solid–fluid interaction, six fluid mixtures with different fluid properties were tested to explore the impacts of fluid properties on the dynamics of free-falling disks and crown formation. Polyacrylamide (PAM) powder was added to water to form fluid mixtures with different fluid densities, viscosities, and yield stresses. The concentration of the additive was varied to change the fluid properties while maintaining the transparency of the fluid for flow visualization. Image analysis techniques were implemented in combination with an in-house MATLAB algorithm to extract information for disk movement, deceleration, and crown geometries, and to study the pinch-off phenomenon. Experimental data indicated that the fluid properties significantly altered the crown formation characteristics and pinch-off properties. Based on the results, the variation of pinch-off time and pinch-off depth versus the fluid entry followed similar trends for all ranges of fluid properties except in relatively low PAM concentration of 0.01 wt.%, where the values of the pinch-off time and pinch-off depth first decreased after increasing the polymer concentration up to 0.01 wt.% and then increased and followed an asymptote. The height of the crown increased at the beginning of the entry, followed by a jump, and it sharply reduced afterward.

7. Standardized Embankment Dam Breach Outflow Hydrograph Uncertainty: Case Study of the 1996 Dyke Failure on the Ha! Ha! River

   Camille Morin, Tewfik Mahdi

   Abstract

   The current practice in dam safety studies is to use standardized breach parameters to produce a breach outflow hydrograph and to map the flood plain. Multiple standards define the width, height, side slope, and formation time of the breach based on a sample of historical dam failures. However, the use of standardized parameters introduces uncertainties in the breach outflow hydrograph which are not estimated in current dam safety studies and may lead to a poor assessment of the dam failure consequences. New probabilistic methods based on a database of historical failures are proposed in the literature to overcome this problem. In this paper, the case study of the 1996 Cut-Away dyke failure on the Ha! Ha! river in the Saguenay region in Quebec is used to demonstrate how the use of standards or probabilistic methods based on historical failures can lead to a poor estimate of the breach outflow hydrograph. A new methodology is proposed to retrieve the breach parameters of historical failures using a gradient-based optimization algorithm and reservoir water levels. This methodology is applied to the 1996 Cut-Away dyke failure. The results show that for this case study, standards and probabilistic methods based on historical events cannot properly predict breach parameters, leading to an underestimation of 85% and 45% of the peak discharge.

8. Unravelling Microplastic Transport in the Gulf of St. Lawrence: Insights from Advanced Hydrodynamic Modelling Using TELEMAC-3D

   Alexander Rey, Abolghasem Pilechi

   Abstract

   The Gulf of St. Lawrence, a stratified tidal estuary, faces growing concerns regarding the distribution and fate of microplastics. To address and respond to these emerging contaminants, improved understanding of their ultimate fate and transport is required. Validated hydrodynamic models coupled with particle tracking have been proposed as a uniquely valuable tool in this regard; however, important questions remain about the necessity of three-dimensional (3D) models compared to two-dimensional (2D) models, validation methodologies, and the applicability of various modelling tools in these environments. This paper presents a comprehensive study on the development and validation of a high-resolution three-dimensional hydrodynamic numerical model to support predicting the fate and transport of microplastics from urban centres to the Atlantic Ocean through a large, continental-scale domain. By leveraging the TELEMAC-3D solver and a high-resolution modelling grid, the study incorporates complex hydrodynamic processes including salinity stratification and spatially and temporally varying flows and winds. The model's performance was validated against a comprehensive dataset encompassing water levels, velocities, and salinity profiles, demonstrating its high computational efficiency and accuracy in simulating the hydrodynamic conditions necessary for supporting microplastic transport investigations. The findings underscore the importance of using three-dimensional modelling to capture the intricacies of vertical variations in velocities and stratification, crucial for accurately predicting microplastic pathways. This research showcases the potential of TELEMAC-3D as a valuable tool for environmental modelling and management, paving the way for future investigations into the impacts of environmental factors on microplastic dispersion.

9. Sanitary Sewer Construction Methodology

   Adekunle Mofolasayo, Otto Hedges, Bernadette Konwat, Daniel Ademola, Sida Wang, Ahmed Hammad

   Abstract

   The choice among three construction methods for sanitary sewer, open-cut construction (for gravity sewers), pilot tube micro-tunneling (for gravity sewers), and lift station with force main (using horizontal directional drilling method for the installation of the underground sewer pipeline), was evaluated through the lens of sustainable construction. Four major aspects of sustainable construction (social, economic, environmental, and technical) were considered to arrive at the most suitable option for this construction. The social aspect considered public safety and odor as relating to how social life in the community will be affected. The economic aspect considered both the construction cost and the operations and maintenance cost. The environmental evaluation considered greenhouse gas production and noise pollution. The technical aspect considered constructability and the use of specialized equipment. Expert interviews were conducted to evaluate the opinion of diverse stakeholders on the project, including Developers, City Engineers, and the Public. Multi-criteria decision-making (MCDM) criteria (Technique for Order of Preference by Similarity to Ideal Solution, TOPSIS) was used to evaluate the responses received. Analysis of the results showed a difference in preference for the construction method. While Developers and the Public preferred the open-trench construction, City Engineers preferred the pilot tube alternative. Overall, from the present analysis, open-trench construction was the preferred choice for construction. The authors would like to note that the decision to choose a specific method of construction for underground sewer lines is site-specific.

10. Residential Resiliency: Flooding Retrofits Case Study

    L. Poirier, B. Ghodoosipour, S. Moretti, P. Knox

    Abstract

    Canadian cities are growing and their density is increasing. These facts combined with increasing global temperatures and a rise in extreme weather events have caused the annual insured losses in Canada due to severe weather events such as floods, ice storms, hurricanes and tornadoes to increase 3.5 times since 2009. This has led to an increased interest in protecting existing homes vulnerable to flooding with retrofits aimed at improving flood resiliency in residential areas. Stakeholders aiming to encourage flood resiliency retrofits have indicated that it is more challenging to justify resiliency retrofits when compared to energy efficiency retrofits because the same tools do not exist to highlight the cost savings or return on investment. For this reason, there is an interest in better understanding the cost-effectiveness of flood resiliency retrofits. In an effort to demonstrate the successes and failures of flood resiliency retrofits in Canada, several case studies are highlighted where the residences have been retrofitted after significant flooding events, the location experienced similar flood conditions, and the retrofits have been evaluated for performance. Support to perform the retrofits is considered as well as obstacles which have made proceeding with retrofits more challenging. These examples help to provide insights into successes and failures in an industry which is required to grow significantly in the near future if Canada is to avoid the economic consequences of continually increasing uninsured losses with a warming climate and increased urban density.

11. Impacts of Suspended Solids on the Formation of FOG (Fat, Oil, and Grease) Deposits

    Xinzai Peng, David Z. Zhu, Wenming Zhang

    Abstract

    The accumulation of fat, oil, and grease (FOG) deposits reduces the hydraulic capacity of sewer networks and ultimately leads to sanitary sewer overflows (SSO) or combined sewer overflows (CSO). To investigate the impacts of suspended solids on the formation of FOG deposits, systematic experiments were conducted in beakers. Oleic and palmitic acids were used as the typical unsaturated and saturated fatty acids, respectively. It was found that the total weight of FOG deposits increases with increasing flow velocity due to the increased mixing. The suspended sand can lead to a significant decrease in the weight of FOG deposits at a relatively low velocity gradient (G < 221.0 s^–1), but its impact gradually diminishes with increasing G. The solids formed from palmitic acid are more adhesive than those from oleic acid. There is a pronounced spatial variation in the percent saponification (S) of the FOG deposits: S is notably higher near the concrete surface and decreases toward the outer layers.

12. An Improved Estimation Model for Dam Failure-Induced Loss of Life

    Samuel Ovi, Mauricio Dziedzic

    Abstract

    The potential loss of life (LOL) resulting from dam failures represents a critical concern in the field of dam safety and disaster management. The accurate estimation of LOL is paramount for informed decision-making, emergency preparedness, and the minimization of human casualties in such catastrophic events. The purpose of this study is to propose an improved model for LOL estimation specific to North American dam failure cases. The study involves a review of existing literature, selecting a model, and refining the chosen model to improve its predictive capabilities for LOL. The approach categorizes dam failure into subcases based on flood severity. It then identifies and filters the more important influencing variables. Subsequently, two empirical equations that serve as the calculation method for LOL formulated through multivariate regression analysis are derived using thirteen dam failure subcases. A comparison with Graham's model shows that the proposed model performs better in predicting LOL. The successful implementation of this model suggests its potential applicability for diverse regions.

13. Prioritizing Investment for Undersized Culverts

    Anna Rice, Carlos Oliveira, Sage Meyers, Tara Yole, Nathan Lepoudre, Mauricio Dziedzic

    Abstract

    Ecosystems across the globe are constantly in a state of change; some from natural causes and some from human causes such as new developments or clearcuts that could impact runoff. Increasing rainfall intensity potentially puts road crossings at risk, including culverts, which may be undersized due to several causes, including climate change. The average lifespan of a culvert in British Columbia, Canada, is 57 years, a period long enough to include land use and climate change impacts on local infrastructure. The primary goal of this work is to determine the prioritization of culvert replacement and/or modification. Essential data include culvert specifications such as location and diameter along with environmental parameters such as precipitation, topography, and stream characteristics. Federal legislation, including the Fisheries Act, and provincial regulations, such as the Forest and Range Practices Act, impact culvert design and maintenance and must be considered. Environmental and social considerations for the proposed prioritization tool include considering if a culvert is placed in a fish-bearing stream and/or sensitive ecosystem, and the highway class and if it is an evacuation route during and after storms. A QGIS Python-based plugin to guide culvert prioritization was developed. The method and associated GIS tool developed can inform budgeting decisions by prioritizing the culverts most at risk, while providing simple culvert assessments with site-specific considerations based on the data available, fostering enhanced infrastructure resilience and ecological preservation in the face of climate and landscape change.

14. Turbulence and Self-Similarity in Classical Hydraulic Jumps

    Mohammadmehdi Ramezani, Shooka Karimpour

    Abstract

    Hydraulic jumps, frequently observed in natural environments and human-made structures like rivers, channels, and dams, are characterized by intense turbulence, air entrainment, and energy dissipation. Given their widespread occurrence and complex flow dynamics, this phenomenon has been widely studied for more than a century through experimental, analytical, and, in more recent years, computational approaches. Turbulence in hydraulic jumps encompasses a wide spectrum of temporal and spatial scales, where near the air–water interface, the surface tension may be of importance, but behind the wavefront, larger scale motions create significant mixing. As a result, computational analysis of such flow requires consideration of several intricacies, making it both challenging and demanding. Reynolds-Averaged Navier–Stokes models are commonly used in the 20 years; however, they aren’t capable of accurately predicting interfacial areas between air and water, i.e., air entrainment and formation and breakup of bubbles. Thanks to recent advancements in computing power, the implementation of high-fidelity and high-resolution turbulence modeling techniques, namely large eddy simulation and direct numerical simulation, has become attainable. This study delves into turbulence and self-similarity in classic stable hydraulic jumps using the large eddy simulation and volume of fluid methods for turbulence modeling and interface capturing. Turbulent structures are resolved up to the Hinze scale with a high temporal frequency, facilitating a full-scale modeling of the phenomena. Ultimately, mean velocities, Reynolds and Favre stresses, alongside self-similarity profiles, will be presented and compared to the experimental results of previous studies, where available.

15. Microplastic Particle Behavior in Turbulent Flows: Insights from Experimental Investigations

    Siamak Seyfi, Ram Balachandar, Shooka Karimpour

    Abstract

    This study delves into the complexities of particle motion within turbulent flows, emphasizing its significance in the fields of hydraulics and hydrodynamics. A focal point of this research is the behavior of microplastics (MPs), which are increasingly recognized for their role as pollutants. The impact of these pollutants on ecosystem health is a major concern, underscoring the urgency of the investigation. MPs, defined as plastic particles ranging in size from less than 5 mm to a few microns, exhibit varied hydrodynamic behaviors due to their diverse characteristics, extending from Stokesian to non-linear Newtonian regimes. To explore the behavior of MPs under turbulent conditions, we employed an open-channel flume to generate controlled turbulence. Within this setup, spherical MP particles of specific sizes were introduced to observe their movement and trajectories using particle reconstruction tracking velocimetry (PRTV) technology. This investigation aims to unravel the dynamics and dispersion patterns of spherical MPs subjected to turbulent flow, utilizing advanced experimental setups to discern the behaviors of particles with different diameters. The findings contribute valuable insights into the transport mechanisms of MPs, enhancing our understanding of their potential impacts on aquatic ecosystems and informing strategies for mitigating pollution.

16. The Hydraulic Impact of the Lateral Dimension of a Flush Headwall on Culvert Inlet Loss

    James A. Kells, Hayden K. Reitenbach

    Abstract

    The Saskatchewan Ministry of Highways has developed a means of reinforcing the inlet of thin-walled pipes, such as that of corrugated steel pipe culverts, so as to minimize the likelihood of an uplift failure and also that of impact damage to the inlet from ice and other debris. For large diameter corrugated steel pipe culverts, the Ministry’s design requires the use of a concrete collar, while for smaller diameters of pipe a steel C-channel is specified. In each case, the end result is akin to that of a flush headwall of ‘modest’ dimension. The Ministry’s current design requirements are that an inlet loss coefficient corresponding to that for a projecting inlet be used, which the Ministry indicates is 0.9, regardless of the use of either the concrete or steel collar. The intent of this work is to learn what minimum dimension of flush headwall is required to allow use of the lower standard flush headwall inlet loss coefficient of 0.5. Any reduction in the inlet loss coefficient may allow for the use of a smaller diameter pipe at a particular installation or provide assurance that the factor of safety against overtopping of the embankment is greater than is currently assumed. The work presented in this study briefly summarizes the findings of a physical model study used to assess the minimum dimension of lateral extension required to yield an inlet loss coefficient typically adopted for a standard flush headwall.

17. Climate Change Uncertainties in Dam Design, Operation, and Management

    Jack W. Warden, Mohammad Fereshtehpour, M. Reza Najafi, Hamidreza Shirkhani

    Abstract

    The increasing hydrological hazards and shifts in degradation mechanisms coupled with a rise in uncertainties in climate-related design factors, present substantial challenges for dam safety, design, and management. As such, it is essential to adapt dam infrastructure to withstand the corresponding risks under a changing climate. Various parameters considered in dam design and operation are susceptible to climate change impacts. For example, temperature fluctuations can lead to internal stresses, freeze–thaw cycling, and alkali-silica reactions in concrete structures. It can also affect soil conditions in earth dams, permafrost, gate function, and more. Future changes in precipitation patterns, compound events, and hydroclimate swings can also lead to safety concerns and are becoming increasingly uncertain as climate changes lead toward more extreme conditions. Further, these uncertainties, coupled with changing extremes, create complexities in dam management and operations, which may ultimately become safety risks. Therefore, it is crucial to identify parameters that influence dam function and operation. This study aims to support the development of a practical framework for dam owners and operators to evaluate risks and generate accurate quantifications of design factors that consider climate uncertainty. The methodology begins with identifying parameters affected by climate change that may impact design, safety, operations, and function through a comprehensive literature review. Through collaboration with stakeholders, additional parameters are determined. Following this, climate projections are used to identify location-specific changes in the climate variables of concern. These projections will serve as the basis for determining the projected climate factors and associated risks in identified design, operation, and management parameters. The determined climatic uncertainties in design and operation parameters will allow dam owners to account for risks to ongoing operations/management and design to enhance resiliency in dams.

18. Unveiling Disparities in Moisture Maximization-Based PMP Estimation Across Canada: The Role of Atmospheric Variables and Long-Term Climatic Trends

    Md. Robiul Islam, Mohammad Reza Najafi, Muhammad Naveed Khaliq

    Abstract

    The traditional physical-based approach for estimating inflow design floods of large dams relies on the moisture maximization technique for estimating probable maximum precipitation (PMP). This procedure involves the direct product of maximum precipitable water and the highest precipitation efficiency derived from historical records. Nevertheless, this approach may overlook the influence of favorable atmospheric conditions that can transform maximum precipitable water into extreme precipitation amounts. Additionally, the formal moisture maximization approach prescribed by the World Meteorological Organization does not account for the long-term climatic trends of PMP components. This study investigates the relationship between seasonal maximum precipitation and corresponding precipitable water using gridded observations spanning the 1940–2021 period across Canada. Utilizing linear regression analysis, we observe a substantial proportion of grid cells showing non-significant relationship during summer, challenging the assumption of a linear conversion rate in moisture maximization-based PMP estimation procedures. Moreover, Mann–Kendall trend analysis reveals significant positive trends in seasonal maximum precipitable water, particularly pronounced during summer, indicating the potential inadequacy of the stationarity assumption for PMP estimation. We further investigate the suitability of additional atmospheric variables, including vertical integrated moisture divergence, vertical velocity, and convective available potential energy, alongside precipitable water. The analysis underscores the importance of considering regional variations in correlations for improving the accuracy of the moisture maximization procedure. These findings highlight the need for revisiting this commonly used procedure for PMP estimation.