BioShock bug?

[Dax]

Not sure if this is the right section, but I can't seem to get past this one point in Neptune's Bounty where there is a gate that separates you from the Upper Wharf and I can't find a way to open it. It is right below the fallen Gatherer's Garden that has crashed through the glass. If you know the place I am talking about, did I skip something or did I do something wrong?

EDIT: I have the 360 version.