If you are close to your home marina, contact the local wharfinger either by phone (you should have his number) or on the marina VHF channel (66, 67, 68? - again, you should know this!).
If you are elsewhere, dial 911, which will get you to JRCC, the Joint Response Control Centre in Victoria.
Alternately, call Victoria Coast Guard on channel 16 who will ask for your location (lat/long) and other pertinent questions, such as are there any other mariners nearby?
Shortly, depending upon the gravity of the situation, they will call out the nearest Canadian Coast Guard unit, or the nearest RCMSAR (Royal Canadian Marine Search and Resue) station.
If you are in need of a tow, and no one else is nearby to help, they may contact a private towing service, who will charge you to defray their costs.