You may want to check your itinerary closely, and if you are travelling around the region, consider working in whale watching a bit further from the big city. A resident pod of orcas hangs out between the Juan de Fuca Straight and Puget Sound, much closer to
Victoria, BC and Anacortes, Wa. Whale watching operators in the vicinity of the local orca pod can virtually guarantee sightings -- they share information and know precisely where the whales are. (See related news story
here.) Vancouver whale watching packages may include airfare or bus to these locations, rather than sailing out in local waters. If your cruise itinerary takes you to Victoria for a day or more, you will probably get a better (and much less expensive) whale watching package than if you travel out of Vancouver.
Whale watching operations in other areas rely on a little more luck / guide skill. Orca's are hunters and will likely be attracted to large populations of prey including sea lions, seals, and large salmon runs (many different river mouths, especially in August), so they may be easier for local guides to find. Humpback Whales feed on krill, herring and other smaller fish. Gray Whales feed on crustaceans found on the ocean floor. However, both Humpback and Gray Whales will likely only be spotted around Vancouver in the the spring or fall as they migrate through local waters on their way to and from their summer feeding grounds off Alaska.