Coming off their wholesale decimation of coal fired powerplants, the EPA is taking on the scourge of the seas.
The Buzzcuts went to the Chicago Boat Show this weekend, and the big news was that 2013 boats with inboards have fuel injected engines with catalysts, to meet new EPA regulations.
Normally, you would find very few boats at the show with outboard motors (which themselves were effected by EPA regulations a few years ago, going from 2 stroke to 4 stroke engines). Outboards have traditionally been much more expensive than inboards (and, thus, have been unpopular in areas like Chicago where boating occurs in fresh water), but not now. I was very surprised to see how many boats now have outboards.
Overall, boats contribute a trivial amount to air pollution, these regulations will mostly cause people like the Buzzcuts to look for a used boat, which will have even worse emissions than a 2012 model year new boat (of which there are still a few out there for sale as new), nevermind the "super clean" 2013 models.