I always just fill up my subzero bottle before heading out and then when I start running low I just head to the water fountains for a refill. I never have a problem finding them, however I have never looked for them on the map to see if they are listed on there. If they are not on the maps maybe it is something for EAA to look into doing. Another good thing about my bottle is I keep it on me so it won't be laying on the ground and blowing across the runways like the disposable plastic bottles.