There was a 4th of July fireworks display promised at Jack London Square on the Oakland estuary. This drew quite a crowd because it was obvious that the really big one on the SF waterfront would be fogged out. A lot of boats (100? 200?) anchored in the middle of the 800 ft wide estuary waiting for the fireworks. This is the second busiest container port on the west coast, and at some point a container ship unberthed and headed up the estuary to the turning basin. A sheriffs boat led the way, sirens and lights, trying to clear the recreational craft from the fairway, most of them anchored. It was sheer chaos. Boats scattering, profanity everywhere. The container ship went on by, and everybody settled down a bit, still waiting. But of course the ship was just going up to the turning basin so it could leave: 30 minutes later, here it comes again the other direction. A full repeat with much more vitriol. I saw several boats fire flares at the bridge of the container ship. Sheriffs boat really couldn't do anything, they had their hands full.