That's ghetto. Maine lobsters are the only way to go.
To have a lobster pot, you have to bait it and leave it on the bottom for a day.
Trap. Lobster trap. Pot is what ya cook 'em in. If you're diving for the damn things you might as well put traps at the bottom, let lobstahs mosey on in, and you don't have to chase 'em around the gosh darned ocean floor all day. You could float your lobstah buoy underwater so it's visible when you're diving.
But the whole idea is just ghetto, illegally trapping lobsters under a bridge; who DOES that?
In the real world (the east coast) illegal trapping is easier, since you can do things like moderately exceeding the trap limit, etc., and it's pretty dang hard for anyone to tell what you're doing unless it's egregious. Still, folks get hauled into court every week for trapping violations, whether for size, number, improper license, whatever.
Forgive me, I'm a Marylander. And we have Crab POTS, and don't do any lobstering :-)
Well, there is actually one guy in Delaware that runs way the hell out on the Continental shelf and does OK with lobster pots...er, traps :-)