Overwintering of Barges in the Beaufort - Assessing Ice Issues and Damage Potential

The report steps through illustrative scenarios, in order to provide examples of the types of ice loads that could occur in representative overwintering locations. These scenarios lead to the provision of a framework of methods used to evaluate ice loads on vessels. This framework can be applied to assess ice loads on a specific vessel with known structural integrity at a specific location, by a team of qualified operational, ice mechanic and naval architect experts. No design considerations are provided, as that assessment would be too case specific to be of use in an overview of this subject area. The authors conclude that a sheltered spot, with a limited fetch area, to limit pack ice driving forces is a key factor to minimizing the likelihood of damage due to ice. It is not sufficient to say that a vessel will be in landfast ice conditions throughout the winter. There are many locations where a vessel may be in landfast ice conditions for most of the winter, but the vessel may be in dynamic conditions come the spring break-up period. During this period, depending upon the location, ice crushing forces on a vessel and/or ice loads can be sufficient to break mooring lines and potentially damage a vessel. Thus, the overwintering location should have minimal dynamic ice movement in the spring, to avoid this scenario. Finally, in order to partially alleviate concerns about the practice of overwintering, and more specifically, overwintering of fuel barges, the authors recommend that the Inuvialuit Settlement Region implement their own record-keeping of fuel barges that are overwintering. This would take the form of a simple record of location, vessel and contact information. Having a record of overwintering, and a method of tracking it, may help to provide more data on the practice, guidance on best practices related to overwintering (such as notification for affected communities and those travelling in the vicinity of the vessel), and peace of mind in terms of sound site selection practices and monitoring.