This topic was addressed about 6 months ago, I think in this forum.
Bottom line is there are rather few ditchings of jet airliners and the reality will likely be rather different than the cartoons in the seatback cards.
The more usual situation for airliners going in the water seems to be overrun. Believe this has happened a few times at LGA, I recall one at Pensacola Fl in the late 70s/early 80s. And then there was Air Florida's spectacular takeoff and aircraft refusal to fly due to ice at DCA.