PhilR, if you google Deception Pass and look at the maps you'll see there is the Pacific Ocean (Straits of Juan DeFuca) on one side and a huge body of water on the other. A lot of water moves through there when the tide is changing. It's the venturi effect of the narrow passage that makes the tide run so fast and boil so much.

Thanks, I'll do that. Looks like the tailwaters of a L&D on the Mississippi. Scary.

It really does boil and you have to watch out for the whirlpools. I t always felt strange how it would bounce the stern back and forth as you go through. I kept the speed up and always considered it a fun run through the pass.

Same thing (whirlpools) when one Ferries over to Vancouver Island from the main land?

I have not taken the Ferrie to Vancouver Island but have boated much of that water. There is a lot of changing water in and around Vancouver Island due to the tidal change. I have seen whirlpools around narrow passages. There are several passages that you can only pass during slack tide. Unless you have a jet boat designed for running up rivers