Why river ice?
That's a good question!
River ice has a significant impact on rivers in northern countries around the world, including most rivers in Canada. Many of these rivers are ice covered for several months out of the year. Therefore, it is very important for engineers to consider the role that river ice can play when working on projects along ice-affected rivers.
What are some of the issues that can be caused by river ice?
I'm glad you asked!
Take freeze-up, for example. Much of the ice that forms in the earliest stages of the river freeze-up process takes the form of small (like, 1 millimetre small!), disc-shaped 'frazil' ice crystals. These crystals form below the water surface and quickly freeze onto anything they come in contact with, including the river bed (forming 'anchor' ice) and human-made objects like water intakes.
These small crystals can cause big problems! Obstructed intakes may need to be shut down for several days until the accumulated frazil ice can be removed, and anchor ice can completely blanket the riverbed and drastically alter or even dam the flow of the river!
There are a lot of other issues caused by river ice as well, including the possibility of ice 'jams' at freeze-up or breakup which can cause severe flooding and damage to communities near the river. In many cases, ice jam floods can be much larger and more severe than open water floods!
So, what are we doing about this?
Another thoughtful question!
One of the best ways to prepare for and mitigate the issues caused by river ice is to predict when and how the ice will form. This is mostly accomplished through the use of numerical river ice models which have been developed by river ice researchers. These models are used to assist with forecasting river ice formation, jamming, and flooding; estimating flow depths and ice thicknesses; and planning the operation of hydroelectric plants (to name just a few!). However, the accuracy of these models can only be validated and improved using data from real-world studies.
That's where I come in! My research is focussed on laboratory and field studies of river ice processes. This includes things like the size and concentration of frazil ice particles, growth rate and thickness of the ice cover, and energy budget of the river during freeze-up. For more information on some of my current projects, read on below!
River Ice Projects
The Freeze-Up Energy BudgetClick to learn more
Frazil ice particles form when the river supercools - that means the water temperature actually falls below its freezing point. Supercooling events can last for several hours or even several days, depending on the environmental conditions. Our ability to predict when supercooling events will occur is critical to our ability to predict how and when the river freeze-up process will unfold.
This is very challenging! The river temperature is dependent on many different variables, including air temperature, wind speed, relative humidity, barometric pressure, cloud cover, and incoming and outgoing radiation (including sunlight). These conditions are very site-specific, so data from the nearest meteorological station are not necessarily accurate enough to predict supercooling events on sub-daily timescales. Additionally, some of these factors (such as cloud cover and radiation) are very rarely measured.
Recently, advances have been made in measuring the heat fluxes at play throughout supercooling events, including a study that I completed together with river ice researchers at the University of Manitoba in 2019. In my current research, I am planning to conduct additional field studies and to compare the field data to remote sensing data. This will include a very detailed study of the surface and subsurface fluxes affecting a small river during freeze-up. The results of this study will be used to support the further development of numerical river ice models, and to provide a forewarning of supercooling events to the operators of water intakes.
Are you interested in studying the energy budget of a river at freeze-up? I'm currently recruiting graduate students for this project!
The Spatiotemporal Variation of Ice Thicknesses in CanadaClick to learn more
One of the most basic characteristics used to describe an ice cover is its thickness. The ice thickness informs many decisions made around river ice, including when it safe to walk, skate, or drive on an ice cover; the ice forces that can be expected and must be designed for on riverine infrastructure such as bridge piers; and the design elevation of submerged objects such as water intakes. However, river ice thicknesses vary based on a large number of variables, and thicknesses are rarely measured throughout the winter.
In this project, I plan to compile historical data of ice thicknesses measured on rivers and lakes across Canada in order to analyse the variation in ice cover thickness across the country and throughout the duration of the historical record. This analysis will be used to provide an easily accessible database of ice thickness data across Canada which can be used by engineers to help inform the design of ice-affected structures. Analysing the variation of ice thicknesses over time will shed light on the impacts of climate change on ice covers throughout the country. Existing equations and models for predicting ice thickness will also be used together with historical meteorological data to develop recommendations and guidelines for accurately predicting river and lake ice thicknesses in different regions of Canada.
In addition to the analysis of historical data, field studies will take place on rivers in Alberta to describe the ice cover and measure ice thicknesses at various characteristic locations (e.g. inside vs. outside of bends, straight reaches, upstream vs. downstream of major infrastructure). This will include measurements of ice thicknesses using ground-penetrating radar (GPR) and ice auguring; collection and crystallographic analysis of ice cores; and measurements of variables impacting ice growth such as meteorological conditions, depth of snow, and flow rates.
Are you interested in studying river and lake ice thicknesses? I am currently looking for enthusiastic graduate students for this project!
Small Embankment Dam BreachClick to learn more
Please Note: I am not currently recruiting graduate students for this project.
What are the consequences associated with the hypothetical failure of a dam? This is a very important question, and in order to answer it we need to be able to estimate how quickly the water contained behind a dam would be released in the event of a breach. This allows us to map out the region that would be flooded by the released water, calculate the maximum flow depths and velocities in the flood zone, and estimate the potential risks to people, property, and the environment in the inundated area.
According to the Alberta Dam and Canal Safety Directive (2018) and Alberta Water Act: Water (Ministerial) Regulation (2021), certain safety regulations must be applied to any dams (even small very small dams) which have certain consequences associated with their failure. The issue is that the existing equations for estimating the flow rate of water resulting from an embankment dam breach have been developed for very large structures. Therefore, these equations may not be appropriate for the analysis of small dams.
This project is focussed on assessing the applicability of existing dam breach equations for small dams, comparing the variations in the consequences of failure estimated using different equations, developing a new equation specifically for small dams, and providing practical recommendations for engineers conducting small dam consequence classifications.