Thanks. Well the vent is on the side right? So somehow the water is running down and around to the side?
I have attached a better picture. The carpet is peeled back and you can see the vent going through the right side of the trunk wall- it's the large black, sort of rectangular thing. There is a void between that trunk wall and the bumper cover- the part of the bumper cover that wraps around to right behind the rear wheel well. The water drains through this void and down to the ground, starting from the opening pointed out at the top of the taillight. So, the water flows along the trunk wall (the outside of the trunk wall in the void space) and down to where the vent punches through into the trunk itself. Water collects into what I have referred to as the "saddlebags", which are on either side of the spare tire well. There is a 3/4" rubber plug at the bottom of each "saddlebag" which is removed in this picture and you can see the hole it plugs into. If the saddlebag fills up with enough water it will spill over into the spare tire well, which I have seen reference to in other threads.
So what is my question anyway?.... Oh yeah- do I have to remove the bumper cover to seal around this vent? And second, is there supposed to be a hose to direct water straight to the ground instead of just running down through the void between the trunk shell and the bumper cover?