We went to South Beach Gardens in Penticton all the time.
http://penticton.travel.bc.ca/listin...rv-park/21989/
http://www.southbeachgardens.net/
It's near south lake in penticton, and when I say near, I mean it's a walk directly across a road. Rentals nearby, waterslides, gokarts. It's technically in the city, but on the SW edge.
edit: Realized you may be looking for more of a partying campground, above might not apply to you then.