From the Gothamist Newsmap:

Found Alligator | Croton Loop & Delmar Loop Brooklyn, NY | 11/28/2006 9:27 a.m.

Man, can you imagine being the person to call 911 about that? Of course, it's no caiman alligator found with a 400 pound tiger in an apartment, but it's still pretty exciting.

Urban legends about alligators in the sewer system tend to be false. And yes, we know that's a picture of Lyle, Lyle Crocodile, but he is a much loved large reptile resident of the city.