Our rules are EXACTLY the same as the US for flight restrictions for liquids.
Quoted from CATS:
"essential non-prescription liquid medications. You are allowed to carry volumes greater than 100 ml (3.4 oz.) in your carry-on baggage. These liquids must be declared to the Screening Officer separately.
Prescription medication
Liquid prescription medications are exempted from the liquid restrictions and can be carried in carry-on baggage in volumes larger than 100 ml (3.4 oz.). These liquids must be declared to the Screening Officer separately.
Inhalers and diabetic supplies are permitted.
Ensure the medication is properly labelled (professionally printed label identifying the medication or a manufacturers name or pharmaceutical label) and displays a matching name with the name printed on the passenger's ticket/boarding pass. "
I had to remove my LINK as I don't have enough posts on this board

If you go to the Canadian Air Transport Security Authority - you can find all the information you'll need.
As for taking water on-board an aircraft - you are right, water in a bottle with a broken seal, is not permitted past security. But once you have passed through security, you are welcome to purchase water (or any other liquid) to bring with you on your flight.
GL with your flight!