Hi,
Biscuits & Bath (
Biscuits and Bath) has puppy social gatherings every Monday at all their locations. I haven't been to any on the UWS but I have been to the one in the UES and its pretty clean (the one on 38th st and 2nd ave is not so clean). Participation is free of charge but you must bring along proof of vaccines. Also, you are expected to look after your dog and remain in the room while they socialize.
Best,
Jessica