but we bring the boat home in March and it is still freezing here in Colorado, so we winterize before leaving. We don't use vodka - I drain our potable lines and then blow them clear. I was just saying it will work in a pinch. I would use it in a potable drinking water system before I would use "Pink" potable anti-freeze as I have found it to be very hard to rid the system of the taste after re-commisioning. I learned this early on in our motor home, few RV'ers I've met will use it in their potable systems - though it works great in heads, holding tanks etc.