Lake Huron, one of North America’s Great Lakes and the third-largest lake in the world, looks placid at times, but it’s a complicated place. Currents, winds, upwelling of water from the depths, heat from the sun and air, plus the effects of human activity along the shore, all impact factors such as water temperature.
Bruce Power, located on the shores of the lake and 220 km west of Toronto, Canada, is the world’s largest nuclear reactor complex by number of reactors. Bruce Power asked Golder to help separate the local heating effects of the plant’s operations from the variable lake-wide natural factors that affect water temperature. This information would provide accurate data for discussions with regulators, local Indigenous communities and other stakeholder groups concerned about possible influences of the facility’s heat profile.
Stretching the limits of current technology to model the lake
To do this, it would not suffice to study just the waters around Bruce Power’s site. Because of the complexity of meteorological, hydrological, anthropological and geo-glacial factors, it would be necessary to model the whole lake (excluding Georgian Bay).
Golder’s work creating an atmospheric-hydrothermal computer-based model for Lake Huron, which received a Canadian Consulting Engineering Award in 2019, leads the way in understanding industrial heat impacts not just on Lake Huron, but potentially on other bodies of water.
To study Lake Huron, Golder developed a computer-based meteorological and hydrodynamic modelling platform, which drives a computational fluid dynamics engine to simulate the water current and heating processes in the lake.
Many similar models rely heavily on local field data, and this can be a problem on Lake Huron in winter, when field data are scarce because field monitors are frequently lost to storms and ice damage. Golder’s model can be operated without lake temperature or current data, relying only on meteorological model data and lake level data from the National Oceanic and Atmospheric Administration (NOAA), United States Army Corps of Engineers, and Environment Canada. Local field data, where and when available, are used to verify the accuracy of the model’s projections.
Opening new possibilities
The benefits of Golder’s model are being realized at many levels within the organization. One of these is enabling Bruce Power to address regulatory and stakeholder concerns in a way they never could before, with verifiable, transparent information on what effects, if any, the site may be having on the Lake Huron nearshore. The information in the model will also support the company in making decisions including long-term capital investments.
The model’s capabilities are being further harnessed to develop a water quality forecasting system that will help Bruce Power with hypothetical spill scenarios. If an unplanned spill were to occur, the company is able to plan its response, track the spill’s movement, and mitigate effects on the fly. The model can help predict the potential timing and magnitude of impact of spills at sensitive receivers according to changing weather and lake conditions.
Going further, the model can be used to look into the past, to understand the processes at work in Lake Huron during times for which field data is either scarce or non-existent. The model can also be configured to understand the future, including the possible effects of climate change, to plan for the long-term sustainability of Bruce Power’s operations.
Golder’s award-winning work not only met the needs of our client but supports a greater understanding of Lake Huron. The technology can and will also be applied to other bodies of water, helping understand the effects of environmental activity in other parts of the country.