Never got thrown in the harbor, but I once rode a bicycle into Los Angeles harbor.
It was a dark and foggy night. The lights at the end of the pier tried valiantly to penetrate the gloom but failed. As I rode along counting cranes so I would know when the end was neigh, suddenly I was airborne. As I sailed through the fog I could only hope jaws wasn't waiting to devour me. (Oh wait that was a few decades before the movie came out).
Suddenly I was submerged. The old (well at the time it was only about four months, but whose going to ruin a good story with facts) training kicked in and I made my way to the surface.
Alas, the fog was so thick I couldn't see the pier. As I was about to panic a SEAL arrived in time to give me a helping hand.
I'll never forget that life altering experience and thank my stars for forlorn arf arf of a heaven sent seal (actually a sea lion, but whose counting).
Post script, I never saw my savior again as he/she slid into the water and swam away into the night. The bicycle was never recovered from Davy Jones locker. And I found out they moved the darned cranes earlier that day.