Research:Djelibeybi crocodile pit
Best way to survive: ditch all your belongings in a vault (everything!), advance off your xp just in case, get a TPA, then go find a militant or zealous priest. With zero burden you will be fine swimming or pushing through reeds. My third time walking out unscathed :)
Cortos, a thief player was able to swim and get through the reeds at 0% burden out of the crocodile pit. He took off all his stuff in the croc pit. His swimming bonus = 125 and grappling bonus = 83. He also mentioned that items he took off would be fished up by the fisherman on the bridge. Seems like not as much grappling + swimming needed if burden is low. He also headed east and avoided the crocs as best as possible.
Quow mentioned that hiding in the rushes is also an option but needs more research?
Also crocs will attack once detect your movement, might want to put that as another note