Yes, several times Usually because as I do not have a dump station at home, the campground s the first place I can flush the lines and tanks, and have a sewer line to carry off the water. If I flush lines at home, it all has to go in the tanks, which means I need to dump anyway. Our irst each year canpground has a good sewage system, and I connected to our local water system, which has good water. So we go with dry tanks, and antifreeze, and leave with fresh water in tanks, lines and water heater, and almost empty grey and black tanks.