Evaluation of the shallow water ice profiling sonar for measuring frazil ice

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The formation of an ice cover in a river is quite different from that on a lake because of the river's current.  The turbulence in the flow causes the formation of a special kind of ice particle, known as frazil ice, which is very 'sticky' when first formed.  These frazil particles tend to stick to each other, to metal screens and racks at water intakes, to rocks on the river bed, and even to vegetation in the river.  This can be a serious problem for hydro-power utilities as well as for municipal and industrial water supplies, since large accumulations of frazil can completely block the intakes, forcing plants to shutdown.  These disruptions to power systems and water supplies have significant socioeconomic costs.At the present time we can detect frazil using a relatively new device known as the Shallow Water Ice Profiling Sonar (SWIPS) which works much like a 'fish finder'.  However, it only indicates the presence of frazil ice and does not provide any measure of the amount of frazil, which is important both for operational purposes (so water intakes can be operated to avoid frazil ice blockage) and for planning purposes (as an input to computer models for predicting ice problems and solutions).  The purpose of the proposed study is to develop a method for making accurate measurements of frazil ice properties, including concentration, using the SWIPS instrument.  This will be achieved by conducting a series of controlled laboratory experiments to determine the quantitative relationship between the SWIPS data and frazil ice properties.  In addition, field data will be collected with the SWIPS in the Athabasca River to demonstrate the application of this new technology in the field.  When coupled with numerical ice process modeling, this will provide validation of the new technology.The findings of this study will reside in the public domain, through publication of the research results in scholarly journals.  Thus the technology will be open to all, and widely available. Given the overwhelming significance of frazil ice deposition and transport to river ice hydraulics and to winter stream ecology the benefits to Canada cannot be overstated.