From a high bridge into water, and here is why. There is a certain height above which bones break even when hitting water, but I think that's beyond bridge-height. Even so, just to make sure, I would arrive feet-first, and I might break both my legs, but I can live through that, I could even swim with arms only. But that "something gross" would probably be thicker than water, I might not be able to properly swim in it, and if it smells really bad, I might reflexively gag or throw up upon being entirely submerged in it, which means I would most likely drown. And that would not be the sort of dignified death I hope for.
Say you have inherited a nice house, but have only a certain amount of time to claim it, you have no car, nor does anyone you know, every form of public transportation is on strike, and it's really far away - would you rather cross the whole country on foot, knowing it's dubious whether you arrive on time, or just give it up?