We presently have a case under consideration by the Manitoba Court of Appeal which may provide some guidance on your question. First, you may wish to get tax advice on the issue of paying capital gains on the expropriation of your principal residence. Generally there is no capital gains tax on your principal residence. Secondly there is an issue of rollover if a replacement property is purchased. You may wish to get advice on that issue also.
If taxes are payable and there is no rollover available, I believe that there is a good argument for reimbursement of those damages under most expropriation legislation.