liveaboards in NYC area
I know a few boats at Brewers Yacht Haven in Stamford Ct do it (are they really "allowed" to I don''t know). For the winter they move the boats all to one protected area and put bubblers on them. This is not an inexpensive marina, but I bet other Brewers Yards do it and other Marina''s.
Go to www.byy.com for more info on Brewers Yacht yards.